Pyrrolo[1,2-c]thiazoles useful as antithrombotic agents

ABSTRACT

Antithrombotics of the formula: ##STR1## wherein A is S, SO or SO 2  ; R 3  is H, alkyl or substituted or unsubstituted phenyl; p is zero or 1; X is O, S, N or variously substituted nitrogen; Y is H or various substituted amines.

The present invention provides new heterocyclic compounds of theformula: ##STR2## in which m represents 1 or 2 and n 0, 1 or 2, the sumof m+n being 1, 2 or 3, A represents sulphur, oxygen, methylene,sulphinyl or sulphonyl, R₃ represents hydrogen, alkyl, or phenyl(unsubstituted or substituted by halogen, alkyl, alkoxy ortrifluoromethyl); and

(a) X represents oxygen or sulphur or an imino or hydroxyimino radical,p represents 0 or 1 and Y represents a radical of the formula: ##STR3##in which R₁ and R₂ both represent hydrogen, or R₁ represents hydrogenand R₂ represents hydroxyl or alkyl of 1 to 5 carbon atoms, which issubstituted by a carboxyl, amino, alkylamino, dialkylamino,hydroxyalkylamino, morpholino or imidazolyl radical, a piperazin-1-ylradical [unsubstituted or substituted in the 4-position by alkyl, benzyl(optionally substituted by a halogen, alkyl, alkoxy or trifluoromethyl)or a phenyl radical (optionally substituted by halogen, alkyl, alkoxy ortrifluoromethyl)] or a piperidino or pyrrolidin-1-yl radical, oralternatively R₂ represents a phenyl radical substituted by one or morehydroxyl, carboxyl, amino, alkylamino or dialkylamino radicals, oralternatively R₁ and R₂ form, with the nitrogen atom to which they arebonded, a 5-membered or 6-membered ring which can also contain anotherheteroatom such as oxygen, sulphur or nitrogen, and which isunsubstituted or substituted by alkyl, alkoxycarbonyl, hydroxyalkyl,aminoalkyl, alkylaminoalkyl or dialkylaminoalkyl, benzyl (optionallysubstituted by halogen, alkyl, alkoxy,trifluoromethyl) or apyrrolidin-1-yl - carbonylalkyl radical, or

(b) X represents dialkylhydrazono, Y represents amino and p represents 0or 1, or

(c) X and Y form with the carbon atom to which they are bondedaδ2-thiazolin-2-ylδ or 2-imidazolin-2-yl radical, and p represents 0 or1, or

(d) X represents oxygen, Y represents hydrogen and p is 0,

the aforesaid alkyl radicals and alkyl portions of other radicals (andthe alkyl radicals and alkyl portions mentioned hereinafter) beingstraight-chain or branched-chain and containing, unless otherwisestated, 1 to 4 carbon atoms, and including the tautomeric forms of thesaid compounds where X represents imino, hydroxyimino ordialkylhydrazono and Y represents a radical of the formula (II) in whichR₁ represents a hydrogen atom, or where X represents oxygen or sulphurand Y represents a radical of the formula (II) in which R₁ represents ahydrogen atom and R₂ represents a hydroxyl radical; and their acidaddition salts and, where they exist, salts with metals andnitrogen-containing bases.

According to a feature of the invention, the compounds of the formula(I) in which m, n, A and R₃ are defined as above and the other symbolsare defined as above under (a), except that X cannot represent a sulphuratom or an imino or hydroxyimino radical, are prepared by reactingammonia or an amine of the formula: ##STR4## in which R₁ and R₂ aredefined as above under (a), with an acid of the formula: ##STR5## inwhich the various symbols are defined as above.

It is particularly advantageous to use the acid of the general formula(IV) in an activated form, such as the acid chloride, or to react itwith N,N'-carbonyldiimidazole or an alkyl chloroformate before reactionwith ammonia or the amine of the general formula (III).

It is generally preferable to react the acid chloride and to carry outthe reaction in an organic solvent such as chloroform or methylenechloride, at a temperature of between 0° C. and the reflux temperatureof the reaction mixture.

The acids of the general formula (IV) can be prepared by hydrolysing thenitriles of the general formula: ##STR6## in which m, n, A and R₃ aredefined as above and p is defined as above under (a), by any methodknown to those skilled in the art for converting a nitrile to an acidwithout affecting the rest of the molecule. It is generally advantageousto carry out the hydrolysis in a basic medium in an alcohol of highb.p., e.g. by means of potassium hydroxide in ethylene glycol, atbetween 100° C. and the reflux temperature of the reaction mixture.

The nitriles of the general formula (V) can be obtained by reacting2-chloroacrylonitrile of the formula: ##STR7## with a product of thegeneral formula: ##STR8## in which the various symbols have thecorresponding definitions.

The reaction is generally carried out in acetic anhydride by heating toa temperature of between 80° and 130° C.

The products of the general formula (VII) can be obtained by condensinga product of the general formula: ##STR9## in which p is equal to 0 or 1and Z_(o) represents an acid-activating group such as a halogen atom,with a product of the general formula: ##STR10## in which R_(o)represents a hydrogen atom or an alkyl radical, this being followed byhydrolysis in the case where R_(o) represents an alkyl radical.

The condensation of the product of the general formula (VIII) with theproduct of the general formula (IX) is generally carried out in an inertorganic solvent such as chloroform, in the presence of an acid acceptorsuch as triethylamine, at a temperature of between 0° and 65° C.

If R_(o) represents an alkyl radical, the hydrolysis is carried out byany method known to those skilled in the art for converting an ester toan acid without affecting the rest of the molecule, in particular bytreatment in an alkaline medium in water or an aqueous-alcoholic solventsuch as a water/ethanol mixture, at a temperature of between 20° and 80°C.

The products of the general formula (IX) can be obtained by applicationor adaptation of the methods described by H. T. NAGASAWA, J. A.ELBERLING, P. S. FRASER and N. S. NIZUNO, J. Med. Chem. 14, 501 (1971),B. BELLEAU, J. Med. Chem. 2, 553 (1960), J. C. WRISTON and C. G.McKENZIE, J. Biol. Chem., 225, 607 (1957), S. WOLFF, G. MILITELLO etal., Tet. Letters, 3913 (1979), H. GERSHON and A. SCALA, J. Org. Chem.26, 2347, (1961), R. RIEMSCHNEIDER and G.A. HOYER, Z. Naturforsch. 17 B,765 (1962), H. MOHRLE and C. KARL, Arch. Pharm, 301, 728 (1968), or R.K. HILL, T. H. CHAN, and J. A. JOULE, Tetrahedron 21, 147 (1965).

If A represents an oxygen atom and n is equal to 0, the product of thegeneral formula (IX) is not isolated but the product of the generalformula (VII) is obtained directly, the condensation of the product ofthe general formula (VIII) being carried out in situ in the reactionmixture.

According to the invention, the products of the general formula (I) inwhich m, n, A and R₃ are defined as above, p is equal to 0 or 1, Xrepresents an oxygen atom and Y represents a radical of the generalformula (II) in which R₁ and R₂ both represent a hydrogen atom can alsobe prepared directly by hydrolysing the nitrile of the general formula(V).

The hydrolysis can be carried out by any means known to those skilled inthe art for converting a nitrile to an amide without affecting the restof the molecule, in particular by heating in an alkaline medium in anorganic solvent such as tert.-butanol, at a temperature of between 30°and 85° C.

According to the invention, the products of the general formula (I) inwhich m, n, A and R₃ are defined as above, p is equal to 0 or 1, Xrepresents an oxygen atom and Y represents a radical of the generalformula (II) in which R₁ and R₂ both represent a hydrogen atom can alsobe prepared by condensing 2-chloroacrylamide of the formula: ##STR11##with an acid of the general formula (VII).

The reaction is generally carried out in acetic anhydride by heating toa temperature of between 80° and 130° C.

According to the invention, the products of the general formula (I) inwhich m, n, A and R₃ are defined as above, p is equal to 0 or 1, Xrepresents a sulphur atom and Y is defined as above under (a), exceptthat it cannot represent a radical of the general formula (II) in whichR₁ represents a hydrogen atom and R₂ represents a hydroxyl radical, canbe prepared by thionating a product of the general formula (I) in whichX represents an oxygen atom and the other symbols have the correspondingmeanings, i.e. a product of the general formula: ##STR12##

The reaction is generally carried out by means of a thionating reagentsuch as phosphorus pentasulphide, in an organic solvent such as toluene,dioxane or pyridine, at a temperature of the order of 100° C., or bymeans of LAWESSON's reagent[2,4-bis-(4-methoxyphenyl)-1,3,2,4-dithiadiphosphetane-2,4-dithione], inan organic solvent such as toluene, at a temperature of the order of 50°C., or such as 1,2-dimethoxyethane or hexamethylphosphoramide, at atemperature of the order of 20° C.

According to the invention, the products of the general formula (I) inwhich m, n, A and R₃ are defined as above, X represents a hydroxyiminoradical and Y and p are defined as above under (a) can be prepared byreacting hydroxylamine with a product of the general formula (I) inwhich m, n, A and R₃ are defined as above, X represents a sulphur atomand Y and p are defined as above under (a), i.e. with a product of thegeneral formula: ##STR13## in which the various symbols have thecorresponding definitions.

Hydroxylamine hydrochloride is generally used and the reaction iscarried out in the presence of mercuric chloride, in pyridine or in anorganic solvent such as ethanol or methanol, in the presence of an acidacceptor such as triethylamine, at a temperature of between 20° and 80°C.

According to the invention, the products of the general formula (I) inwhich m, n, A and R₃ are defined as above, X represents an imino radicaland Y and p are defined as above under (a) can be prepared by reactingammonia or an amine of the general formula (III) in which R₁ and R₂ aredefined as above, with an iminothioether of the general formula:##STR14## in which R represents an alkyl radical, preferably methyl, m,n, A and R₃ are defined as above and p is defined as above under (a).

The reaction is generally carried out in an organic solvent such aschloroform, in the presence of a weak acid such as acetic acid, at atemperature of between 20° and 65° C.

The iminothioether of the general formula (XIII) can be prepared byreacting an alkyl halide of the general formula:

    R--Z                                                       (XIV)

in which R is defined as above and Z represents a halogen atom,preferably an iodine atom, with a product of the general formula (I) inwhich m, n, A and R₃ are defined as above, p is equal to 0 or 1, Xrepresents a sulphur atom and Y represents a radical of the generalformula (II) in which R₁ and R₂ both represent a hydrogen atom, i.e. aproduct of the general formula: ##STR15## in which the various symbolshave the corresponding definitions.

The reaction is generally carried out in an organic solvent such asacetone or a mixture of acetone and dimethylformamide, at a temperatureof between 0° and 50° C.

According to the invention, the products of the general formula (I) inwhich m, n, A and R₃ are defined as above, X represents a sulphur atom,Y represents a radical of the general formula (II) in which R₁ and R₂both represent a hydrogen atom and p is equal to 0, i.e. a product ofthe general formula (XV) in which the symbols have the correspondingdefinitions, can be prepared from the nitriles of the general formula(V) by any method known to those skilled in the art for converting anitrile to a thioamide without affecting the rest of the molecule. It isparticularly advantageous to react hydrogen sulphide with the nitrile ofthe general formula (V), in a solvent such as pyridine, in the presenceof triethylamine, at a temperature of between 0° and 50° C.

According to the invention, the products of the general formula (I) inwhich m, n, a and R₃ are defined as above and X, Y and p are defined asabove under (b) can be prepared by reacting a dialkylhydrazine of thegeneral formula: ##STR16## in which R' and R" represent identical ordifferent alkyl radicals, with an iminothioether of the general formula(XIII) in which the symbols have the corresponding definitions.

The reaction is generally carried out in an organic solvent such asethanol, at a temperature of between 20° and 80° C.

According to the invention, the products of the general formula (I) inwhich m, n, A and R₃ are defined as above, p is equal to 0 or 1, Xrepresents an oxygen atom and Y represents a radical of the generalformula (II) in which R₁ represents a hydrogen atom and R₂ represents analkyl radical containing 1 to 5 carbon atoms, which is substituted by ahydroxyalkylamino radical, it being understood that the alkyl radicaland the alkyl portion of the hydroxyalkylamino radical contain the samenumber of carbon atoms, can also be prepared by reacting an aminoalcohol of the general formula:

    H.sub.2 N--Q--OH                                           (XVII)

in which Q represents an alkylene radical containing 1 to 5 carbonatoms, with a nitrile of the general formula (V).

The reaction is generally carried out in an excess of aminoalcohol ofthe general formula (XVII), in the presence of lithium chloride and at atemperature of between 100° C. and the reflux temperature of thereaction mixture.

According to the invention, the products of the general formula (I) inwhich m, n, A and R₃ are defined as above and X, Y and p are defined asabove under (c) can be prepared by reacting a product of the generalformula:

    H.sub.2 NCH.sub.2 CH.sub.2 --T--H                          (XVIII)

in which T represents a sulphur atom or an imino radical, with a nitrileof the general formula (V).

The reaction is generally carried out in an organic solvent such as analcohol, or in an excess of the products of the general formula (XVIII),at a temperature of between 60° C. and the reflux temperature of thereaction mixture.

According to the invention, the products of the general formula (I) inwhich m, n, A and R₃ are defined as above, X and Y form aΔ2-imidazolinyl radical with the carbon atom to which they are bondedand p is equal to 0 can also be prepared by reacting ethylenediaminewith a dithioester of the general formula: ##STR17## in which Rrepresents an alkyl radical and the other symbols are defined as above.

The reaction is generally carried out in an excess of ethylenediamine,in the presence of mercuric chloride, at a temperature of between 60° C.and the reflux temperature of the reaction mixture.

The dithioesters of the general formula (XIX) can be prepared byreacting hydrogen sulphide with a product of the general formula (XIII)in which the symbols have the corresponding definitions.

The reaction is generally carried out in a solvent such as pyridine, ata temperature of the order of 20° C.

According to the invention, the products of the general formula (I) inwhich m, n, A and R₃ are defined as above and X, Y and p are defined asabove under (d) can be prepared by formylating a product of the generalformula: ##STR18## in which the symbols are defined as above.

The formylation is generally carried out by any means known to thoseskilled in the art for formylating a pyrrole nucleus without affectingthe rest of the molecule, in particular by means of a mixture ofphosphoryl chloride and dimethylformamide, at a temperature of between0° C. and 20° C.

The products of the general formula (XX) can be prepared bydecarboxylating an acid of the general formula (IV) in which p is equalto 0 and the other symbols are defined as above, by the methods whichare in themselves known for decarboxylating an acid, e.g. by heating inthe presence of copper powder.

According to the invention, the products of the general formula (I) inwhich A represents a sulphinyl or sulphonyl radical and the othersymbols are defined as above, except that X cannot represent a sulphuratom and p cannot be equal to 1, can be prepared by oxidising a productof the general formula (I) in which A represents a sulphur atom and theother symbols are defined as above, i.e. a product of the generalformula: ##STR19## by any means known to those skilled in the art forconverting a sulphide to a sulphoxide or a sulphone without affectingthe rest of the molecule.

The oxidation can be carried out e.g. by employing a reagent commonlyused for converting a sulphide to a sulphoxide or a sulphone, thereaction being carried out in a suitable solvent. By way of example, itis possible to use hydrogen peroxide in acetone or acetic acid, analkali metal periodate in an alcohol or acetonitrile, or a percarboxylicacid (peracetic, perbenzoic, m-chloroperbenzoic, p-nitroperbenzoic orperphthalic acid) in an ether (dioxane, tetrahydrofuran or diethylether), a chlorinated solvent (methylene chloride or dichloroethane),acetic acid or a mixture of these solvents. The reaction is generallycarried out at a temperature of between -10° and +20° C.

It is particularly advantageous to carry out the reaction in a mixtureof acetic acid and methylene chloride, in the presence ofm-chloroperbenzoic acid, at a temperature of between -10° and 0° C.

If it is desired to obtain the sulphoxide, it is necessary to carry outthe reaction with one equivalent of oxidising agent. If it is desired toobtain the sulphone, it is necessary to use at least two equivalents ofoxidising agent. The actual oxidation reaction is carried out in thepresence of at least one equivalent of an acid such as methanesulphonicacid, at a temperature of the order of 20° C.

According to the invention, the products of the general formula (I) inwhich A represents a sulphinyl or sulphonyl radicaL, X represents asulphur atom, p is equal to 0 and the other symbols are defined as abovecan be prepared by reacting ammonia or an amine of the general formula(III) with a dithioester of the general formula: ##STR20## in which Rrepresents an alkyl radical, q is equal to 1 or 2 and the other symbolsare defined as above.

The reaction is generally carried in an organic solvent such as ethanol,at a temperature of between 20° C. and the reflux temperature of thereaction mixture.

The dithioesters of the general formula (XXII) can be prepared byoxidising a product of the general formula (XIX) in which A represents asulphur atom and p is equal to 0, i.e. a product of the general formula:##STR21## in which R represents an alkyl radical and R₃, m and n aredefined as above.

The oxidation is generally carried out under the conditions referred toabove for oxidising a product of the general formula (XXI).

According to the invention, the products of the general formula (I) inwhich m, n, A and R₃ are defined as above, X and p are defined as aboveunder (a) and Y represents a radical of the general formula (II) inwhich R₁ represents a hydrogen atom and R₂ represents an alkyl radicalcontaining 1 to 5 carbon atoms, which is substituted by a carboxylradical, can also be prepared by hydrolysing a product of the generalformula: ##STR22## in which m, n, A, X, R₃ and p have the correspondingdefinitions, Alc represents an alkyl radical and W represents analkylene radical containing 1 to 5 carbon atoms.

The reaction is carried out by any means known to those skilled in theart for converting an ester to an acid without affecting the rest of themolecule, in particular by saponification by means of an alkali metalhydroxide such as sodium hydroxide or potassium hydroxide, in an alcoholsuch as ethanol.

The products of the general formula (XXIV) can be prepared by reactingan aminoester of the general formula:

    H.sub.2 N--W--COOAlc                                       (XXV)

in which Alc represents an alkyl radical and W represents an alkyleneradical containing to 1 to 5 carbon atoms, with a product of the generalformula (IV) if it is desired to obtain the product of the generalformula (XXIV) in which X represents an oxygen atom, this beingfollowed, if appropriate, by thionation if it is desired to obtain aproduct of the general formula (XXIV) in which X represents a sulphuratom, or alternatively with a product of the general formula (XIII) ifit is desired to obtain a product of the general formula (XXIV) in whichX represents an imino radical.

The reaction can be carried out under the same conditions as thosereferred to above for reacting a product of the general formula (III)with a product of the general formula (IV) or (XIII).

It is understood by those skilled in the art that, to carry out theprocesses according to the invention which have been described above, itmay be necessary to introduce groups for protecting the functionalgroups which may be present in the various radicals, in order to preventsecondary reactions. In particular, if a carboxyl or alkoxy carbonylgroup is present in the radical R₂, it may be necessary to block thesaid group, e.g. in the form of a 4,4-dimethyl-1,3-oxazoline, and thento regenerate the group by hydrolysis in an aqueous or alcoholic mediumafter the appropriate process has been carried out. Likewise, if anamino or alkylamino group is present in this radical, it may benecessary to block the said group, e.g. in the form of atrifluoromethylacetamide, and then to regenerate the group by reactionwith ammoniacal methanol after the appropriate process has been carriedout.

Likewise, if X represents at oxygen atom and Y represents a hydrogenatom, and if it is desired to oxidise a product of the general formula(XXI), it is necessary to block the aldehyde group before carrying outthe oxidation, e.g. in the form of an acetal, and then to unblock thealdehyde group by the usual methods.

The new products of the general formula (I) can be purified by the usualknown methods, e.g. by crystallisation, chromatography or successiveextractions in acidic and basic media.

The compounds of formula (I) can be converted into acid addition saltsby reaction with an acid in an organic solvent such as an alcohol, aketone, an ether or a chlorinated solvent. The salt formed precipitates,if necessary after concentration of its solution. It may be separatedoff by filtration or decantation.

The compounds of formula (I) in which Y represents a radical of theformula (II) in which R₁ represents a hydrogen atom and R₂ represents ahydroxyl radical, an alkyl radical containing 1 to 5 carbon atoms, whichis substituted by a carboxyl radical, or a phenyl radical substituted byone or more carboxyl radicals can be converted into metal salts oraddition salts with nitrogen bases by any method known to those skilledin the art for carrying out this conversion which does not affect therest of the molecule.

The compounds of formula (I) and their salts possess valuablepharmacological properties, and in particular are useful in theprophylactic and therapeutic treatment of thrombotic complaints. In thetest for measuring the in vitro inhibiting activity against plateletaggregation caused by collagen, (using the technique of G. V. R. BORN etal., J. Physiol. 168, 178 (1963)), they have been shown to be active atconcentrations of less than 50 mg/liter.

The compounds of formula (I) and their salts also have a low toxicity.Their LD₅₀ is generally between 300 and 900 mg/kg, when administeredorally to mice.

Of particular value are the compounds of the formula (I) in which m is 1or 2 and n is zero or 1, A represents sulphur, methylene or sulphonyl,R₃ represents hydrogen, alkyl or phenyl, and

X represents oxygen, sulphur, imino or hydroxyimino, p is 0 or 1 and Yrepresents a radical of the formula: ##STR23## in which R₁ and R₂ bothrepresent a hydrogen atom, or alternatively R₁ represents a hydrogenatom and R₂ represents a hydroxyl radical or an alkyl radical containing1 to 5 carbon atoms, which is substituted by a carboxyl, dialkylamino,hydroxyalkylamino, morpholino or imidazolyl radical or by apiperazin-1-yl radical substituted in the 4-position by alkyl, oralternatively R₁ and R₂ form, with the nitrogen atom to which they arebonded, a 6-membered ring which can also contain another hetero atomsuch as oxygen or nitrogen, and which is unsubstituted or substituted byalkyl, hydroxyalkyl, benzyl or pyrrolidin-1-yl-carbonylalkyl, or

X represents dialkylhydrazono, Y represents amino and p is zero, or

X and Y form a Δ2-thiazolin-2-yl or Δ2-imidazolin-2-yl radical with thecarbon atom to which they are bonded and p is 0, or

X represents oxygen, Y represents hydrogen and p is 0.

Of more particular value are the compounds of formula (I) in which m is1 or 2 and n is zero, A represents sulphur, methylene or sulphonyl, R₃represents a hydrogen atom and

X represents oxygen, sulphur, imino or hydroxyimino, p is 0 or 1 and Yrepresents a radical of the formula: ##STR24## in which R₁ and R₂ bothrepresent a hydrogen atom, or R₁ represents a hydrogen atom and R₂represents hydroxy or dialkylaminoethyl, or R₁ and R₂ form, with thenitrogen atom to which they are bonded, a 6-membered ring which can alsocontain another hetero atom such as nitrogen, and which is unsubstitutedor substituted by alkyl or benzyl, or

X represents dialkylhydrazono, Y represents amino and p is zero, or

X and Y with the carbon atom to which they are bonded form aΔ2-thiazolin-2-yl radical, or

X represents oxygen, Y represents hydrogen and p is zero.

Of especial value are the compounds of formula (I) in which m represents1 or 2 and n represents zero, A represents sulphur, methylene orsulphonyl, R₃ represents hydrogen, p is zero, and

X represents oxygen, sulphur or hydroxyimino, and Y represents a radicalof the formula: ##STR25## in which R₁ and R₂ both represent hydrogen, oralternatively R₁ and R₂ form, with the nitrogen atom to which they arebonded, a piperazin-1-yl ring unsubstituted or substituted by methyl, or

X represents dialkylhydrazono and Y represents amino.

The following compounds are of particular value:

5-(pyridin-3-yl)-1H,3H-pyrrolo-[1,2-c]thiazole-7-carboxamide;

6-(pyridin3-yl)-1,2-dihydro-4H-pyrrolo-[1,2-c]-1,3-thiazine-8-carboxamide;

5-(pyridin-3-yl)-2,3-dihydro-1H-pyrrolizine-7-carboxamide;

3-(pyridin-3-yl)-5,6,7,8-tetrahydroindolizine-1-carboxamide;

5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazole-7-carbothioamide;

5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazole-7-carboxamide 2,2-dioxide;

7-[(4-methylpiperazin-1-yl)-carbonyl]-5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazole;

5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazole-7-carboxamide-oxime;

5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazole-7-carboxamide-dimethylhydrazone;and

7-(piperazin-1-yl-carbonyl)-5-(pyridin-3-yl)-1H,3H-pyrrolo[-1,2-c]thiazole.

For medicinal purposes, the compounds of formula (I) can be used as suchor in the form of pharmaceutically acceptable salts, i.e. salts whichare non-toxic at the doses used.

Examples of pharmaceutically acceptable salts which may be mentioned arethe addition salts with mineral acids, such as the hydrochlorides,sulphates, nitrates and phosphates, or with organic acids, such as theacetates, propionates, succinates, benzoates, fumarates, maleates,methanesulphonates, isethionates, theophyllineacetates, salicylates,phenolphthaleinates and methylene-bis-β-oxynaphthoates, or substitutionderivatives of these compounds. Where they exist, salts formed withbases may be used, for example salts with alkali metals, such as thesodium, potassium or lithium salts, and with alkaline earth metals, suchas the calcium or magnesium salts, and the addition salts with organicbases, such as the ethanolamine or lysine salts.

The Examples which follow illustrate the invention.

EXAMPLE 1

A suspension of5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazole-7-carbonitrile (11.35 g)and powdered potassium hydroxide (14 g) in tert.-butyl alcohol (100 cc)is heated at 85° C. for 1 hour. After stirring for 16 hours at atemperature of the order of 20° C., the reaction mixture is poured intodistilled water (2 liters). The suspension is stirred at a temperatureof the order of 20° C. for 15 minutes and the crystals which haveappeared are then filtered off, washed 8 times with distilled water(1,200 cc in total) and then 3 times with ethanol (150 cc in total) anddried under reduced pressure (20 mm Hg; 2.7 kPa) at a temperature of theorder of 20° C., in the presence of potassium hydroxide pellets. Thisgives a crude product (10.5 g), which is combined with a productprepared in the same way in an earlier operation (3.9 g) and dissolvedin boiling ethanol (850 cc). The solution is treated with decolourisingcharcoal (0.5 g) and filtered hot. The filtrate is cooled at atemperature of the order of 4° C. for 3 days. The crystals which haveappeared are filtered off, washed 3 times with ethanol cooled to atemperature of the order of 4° C. (30 cc in total) and dried underreduced pressure (20 mm Hg; 2.7 kPa) at a temperature of the order of20° C., in the presence of potassium hydroxide pellets. This gives5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazole-7-carboxamide (11.3 g) inthe form of cream crystals melting at 215° C.

The 5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazole-7-carbonitrile can beprepared in the following manner:

A suspension of N-nicotinoylthiazolidine-4-carboxylic acid (403 g) in amixture of 2-chloroacrylonitrile (1,350 cc) and acetic anhydride (1,750cc) is heated at 90° C. for 2 hours 40 minutes. During this period, themixture is seen to pass through a clear homogeneous phase after 30minutes, this being followed by precipitation 10 minutes later. Aftercooling at a temperature of the order of 4° C. for 16 hours, thecrystals which have appeared are filtered off, washed twice with aceticanhydride (200 cc in total) and 3 times with acetone (300 cc in total)and dried under reduced pressure (20 mm Hg; 2.7 kPa) at a temperature ofthe order of 20° C., in the presence of potassium hydroxide pellets. Theproduct thus obtained is suspended in a 2N aqueous solution of sodiumhydroxide (2,400 cc). After stirring at a temperature of the order of20° C. for 1 hour 30 minutes, the crystals which have appeared arefiltered off, washed 5 times with distilled water (1,250 cc in total), 3times with ethanol (1,200 cc in total) and 3 times with diethyl ether(900 cc in total) and dried under reduced pressure (20 mm Hg; 2.7 kPa)at a temperature of the order of 20° C., in the presence of potassiumhydroxide pellets. This gives5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazole-7-carbonitrile (159.7 g)in the form of cream crystals melting at 170° C.

The N-nicotinoylthiazolidine-4-carboxylic acid can be obtained in thefollowing manner:

Nicotinoyl chloride hydrochloride (534 g) is added in the course of 1hour, at a temperature of between 30° and 52° C., to a solution ofthiazolidine-4carboxylic acid (400 g) and triethylamine (613 g) inchloroform (4,500 cc). The solution obtained is heated at a temperatureof the order of 64° C. for 4 hours. After stirring at a temperature ofthe order of 20° C. for 16 hours, the crystals which have appeared arefiltered off, washed 3 times with chloroform (1,500 cc in total) andthen 3 times with diethyl ether (1,500 in total) and dried under reducedpressure (20 mm Hg; 2.7 kPa) at a temperature of the order of 20° C., inthe presence of potassium hydroxide pellets. This givesN-nicotnoylthiazolidine-4-carboxylic acid (403 g) in the form of whitecrystals melting at 190° C.

EXAMPLE 2

A suspension of5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazole-7-carbonitrile (22.7 g) ina mixture of triethylamine (14 cc) and pyridine (32 cc) is saturated for5 hours, at a temperature of the order of 20° C., with a gaseous streamof hydrogen sulphide. After stirring at a temperature of the order of20° C. for 3 days, pyridine (32 cc) is added to the reaction mixture,the suspension is saturated again for 8 hours, at a temperature of theorder of 20° C., with a gaseous stream of hydrogen sulphide and thestirring is then continued for 16 hours at a temperature of the order of20° C. The same operation is repeated twice. The suspension is saturatedagain for a further 3 hours, at a temperature of the order of 20° C.,with a gaseous stream of hydrogen sulphide and the reaction mixture isthen poured into distilled water (500 cc). The crystals which haveappeared are filtered off, washed 4 times with distilled water (200 ccin total), then twice with ethanol (100 cc in total) and then twice withisopropyl ether (100 cc in total) and dried under reduced pressure (20mm Hg; 2.7 kPa) at a temperature of the order of 20° C., in the presenceof potassium hydroxide pellets. This gives a crude product (26 g)melting at 230° C. This product is dissolved in dimethylformamide (250cc) at a temperature of the order of 100° C. The solution obtained istreated with decolourising charcoal (1 g) and filtered hot; the filtrateis cooled at a temperature of the order 4° C. for 2 hours. The crystalswhich have appeared are filtered off, washed twice withdimethylformamide (40 cc in total), 3 times with ethanol (150 cc intotal) and then 3 times with isopropyl ether (150 cc in total) and driedunder reduced pressure (20 mm Hg; 2.7 kPa) at a temperature of the orderof 20° C., in the presence of potassium hydroxide pellets. This gives5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazole-7-carbothioamide (21 g) inthe form of yellow crystals melting at 243° C.

The 5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazole-7-carbonitrile isprepared as described in Example 1.

EXAMPLE 3

A suspension of 5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazole-7-carboxylic acid (8.8 g) in a mixture of thionylchloride (6.25 cc), dimethylformamide (0.05 cc) and 1,2-dichloroethane(100 cc) is heated under reflux for 2 hours 30 minutes, with stirring.The reaction mixture is cooled to a temperature of the order of 20° C.and concentrated to dryness under reduced pressure (20 mm Hg; 2.7 kPa)at a temperature of the order of 60° C. The residue obtained issuspended in cyclohexane (150 cc) and the solvent is evaporated offunder reduced pressure (20 mm Hg; 2.7 kPa) at a temperature of the orderof 60° C. The same operation is repeated twice. This gives7-chloroformyl-5-(pyridin-3-yl)-pyrrolo[1,2-c]thiazole hydrochloride (10g) in the form of cream crystals melting at 220° C.

This product is taken up in methylene chloride (200 cc). A solutioncontaining N-(3-aminopropyl)-morpholine (6.2 g) and triethylamine (8.7g) in methylene chloride (70 cc) is then added to the solution thusobtained in the course of 20 minutes, at a temperature of between 23 and31° C. The resulting solution is stirred at a temperature of the orderof 20° C. for 16 hours. Methylene chloride (250 cc) and distilled water(250 cc) are added to the solution. The organic phase is separated off,washed twice with distilled water (500 cc in total), treated withdecolourising charcoal (0.5 g), dried over anhydrous magnesium sulphateand filtered, and the iiLtrate is concentrated to dryness under reducedpressure (20 mm Hg; 2.7 kPa) at a temperature of the order of 60° C.This gives a crude oil (1.6 g). This product is combined with a productprepared in the same way in a previous operation (2.7 g) and isdissolved in boiling propan-2-ol (150 cc). Decolourising charcoal (0.5g) is added to the solution obtained and the mixture is filtered hot.The filtrate is cooled at a temperature of the order of 4° C. for 1hour. The crystals which have appeared are filtered off, washed 3 timeswith propan-2-ol (30 cc in total) and 3 times with isopropyl ether (75cc in total) and dried under reduced pressure (20 mm Hg; 2.7 kPa) at atemperature of the order of 20° C., in the presence of potassiumhydroxide pellets. This gives a product (11.6 g) melting at 156° C. Thisproduct is dissolved in boiling ethanol (50 cc). Decolourising charcoal(0.5 g) is added to the solution obtained and the mixture is filteredhot. The filtrate is cooled at a temperature of the order of 4° C. for 1hour. The crystals which have appeared are filtered off, washed twicewith ethanol (10 cc in total) and then 3 times with isopropyl ether (75cc in total) and dried under reduced pressure (20 mm Hg; 2.7 kPa) at atemperature of the order of 20° C., in the presence of potassiumhydroxide pellets. This gives a product (10.5 g) melting at 158° C. Thisproduct is dissolved in boiling acetonitrile (200 cc). The solutionobtained is filtered hot and the filtrate is then cooled at atemperature of the order of 4° C. for 15 minutes. The crystals whichhave appeared are filtered off, washed 3 times with acetonitrile (45 ccin total) and 3 times with isopropyl ether (75 cc in total) and driedunder reduced pressure (20mm Hg; 2.7 kPa) at at temperature of the orderof 20° C., in the presence of potassium hydroxide pellets. This givesN-(3-morpholinopropyl)-5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazole-7-carboxamide(9 g) in the form of cream crystals melting at 158° C.

The 5-(pyridin-3.yl)-1H,3H-pyrrolo[1,2-c]thiazole-7-carboxylic acid canbe prepared in the following manner:

A mixture of5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazole-7-carbonitrile (18.7 g),potassium hydroxide pellets (16.3 g) and ethylene glycol (160 cc) isheated at a temperature of the order of 155° C. for 2 hours, withstirring. After stirring for 16 hours at a temperature of the order of20° C., the solvent is evaporated off under reduced pressure (2 mm Hg;0.27 kPa) at a temperature of the order of 100° C. The residue isdissolved in distilled water (100 cc) and the solution obtained isbrought to a pH of the order of 5 by adding a 2 N aqueous solution ofhydrochloric acid. The crystals which have appeared are filtered off,washed 3 times with distilled water (150 cc in total) and then 3 timeswith acetone (150 cc in total) and dried under reduced pressure (20 mmHg; 2.7 kPa) at a temperature of the order of 20° C., in the presence ofpotassium hydroxide pellets. This gives a crude product (17.7 g) meltingat 264° C. This product is combined with a product prepared in the sameway in a previous operation (1.3 g) and dissolved in a mixture ofbutan-1-ol (650 cc) and dimethylformamide (150 cc), heated beforehand toa temperature of the order of 115° C. Decolourising charcoal (0.5 g) isadded to the solution obtained and the mixture is filtered hot. Thefiltrate is cooled at a temperature of the order of 4° C. for 16 hours.The crystals which have appeared are filtered off, washed twice withdimethylformamide (50 cc in total), 3 times with ethanol (150 cc intotal), 3 times with isopropyl ether (150 cc in total) and then 3 timeswith diethyl ether (150 cc in total) and dried under reduced pressure(20 mm Hg; 2.7 kPa) at a temperature of the order of 20° C., in thepresence of potassium hydroxide pellets. This gives a product (16.1 g)melting at 266° C. This product is suspended in distilled water (250 cc)and the suspension is stirred at a temperature of the order of 20° C.for 2 hours. The crystals are filtered off, washed 5 times withdistilled water (150 cc in total), 3 times with ethanol (90 cc intotal), 3 times with isopropyl ether (90 cc in total) and then 3 timeswith diethyl ether (90 cc in total) and dried under reduced pressure (20mm Hg; 2.7 kPa) at a temperature of the order of 100° C., in thepresence of potassium hydroxide pellets. This gives5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazole-7-carboxylic acid (15.5 g)in the form of cream crystals melting at 266° C.

The 5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazole-7-carbonitrile isprepared as in Example 1.

EXAMPLE 4

A solution of N-methylpiperazine (13.2 g) in methylene chloride (120 cc)is added in the course of 20 minutes, at a temperature of between 22 and30° C., to a suspension of7-chloroformyl-5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazolehydrochloride (12.5 g) in methylene chloride (250 cc). The solutionobtained is stirred at a temperature of the order of 20° C. for 16hours. Methylene chloride (250 cc) and distilled water (150 cc) are thenadded. The organic phase is separated off by decantation, washed twicewith distilled water (300 cc in total), dried over anhydrous magnesiumsulphate, treated with decolourising charcoal (0.5 g) and filtered, andthe filtrate is concentrated to dryness under reduced pressure (20 mmHg; 2.7 kPa) at a temperature of the order of 60° C. The hard foamobtained is taken up in isopropyl ether (150 cc) for 1 hour at atemperature of the order of 20° C., with stirring. After 24 hours atthis temperature, the crystals which have appeared are filtered off,washed 3 times with isopropyl ether (75 cc in total) and dried underreduced pressure (20 mm Hg; 2.7. kPa) at a temperature of the order of20° C., in the presence of potassium hydroxide pellets. This gives acrude product (10.8 g) melting at 90° C. This product is dissolved inboiling carbon tetrachloride (250 cc). Decolourising charcoal (0.5 g) isadded to the solution obtained and the mixture is filtered hot; thefiltrate is cooled at a temperature of the order of 4° C. for 16 hours.The crystals which have appeared are filtered off, washed 3 times withcarbon tetrachloride (30 cc in total) and then 4 times with isopropylether (100 cc in total) and dried under reduced pressure (20 mm Hg; 2.7kPa) at a temperature of the order of 20° C., in the presence ofpotassium hydroxide pellets. This gives a product (5.8 g) melting at104° C. This product (5.4 g) is dissolved in boiling acetonitrile (12cc). The solution obtained is cooled at a temperature of the order of 4°C. for 2 hours. The crystals which have appeared are filtered off,washed 3 times with acetonitrile (6 cc in total) and 3 times withisopropyl ether (30 cc in total) and dried under reduced pressure (20 mmHg; 2.7 kPa) at a temperature of the order of 20° C., in the presence ofpotassium hydroxide pellets. This gives7-[(4-methylpiperazin-1-yl)-carbonyl]-5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazole(4 g) in the form of cream crystals melting at 108° C.

The 7-chloroformyl-5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazolehydrochloride is prepared as in Example 3.

EXAMPLE 5

A suspension of5-(pyridin-3-yl)-2,3-dihydro-1H-pyrrolizine-7-carbonitrile (14.6 g) andpowdered potassium hydroxide (23.1 g) in tert.-butyl alcohol (140 cc) isheated at 82° C. for 2 hours. During this period, the mixture is seen topass through a clear homogeneous phase after 10 minutes, this beingfollowed by precipitation 20 minutes later. After cooling to atemperature of the order of 20° C., the solvent is evaporated off underreduced pressure (20 mm Hg; 2.7 kPa) at a temperature of the order of60° C. The crystalline residue obtained is suspended in distilled water(250 cc) and the suspension is stirred at a temperature of the order of20° C. for 30 minutes. The crystals are filtered off, washed 4 timeswith distilled water (200 cc in total) and then 3 times with isopropylether (150 cc in total) and dried reduced pressure (20 mm Hg; 2.7 kPa)at a temperature of the order of 20° C., in the presence of potassiumhydroxide pellets. This gives a crude product (15.5 g) melting at 206°C. This product is dissolved in boiling ethanol (150 cc). The solutionobtained is treated with decolourising charcoal (0.5 g) and filtered;the filtrate is cooled at a temperature of the order of 10° C. for 2hours. The crystals are filtered off and dried under reduced pressure(20 mm Hg; 2.7 kPa) at a temperature of the order of 20° C., in thepresence of potassium hydroxide pellets. This gives5-(pyridin-3-yl)-2,3-dihydro-1H-pyrrolizine-7-carboxamide (9.6 g) in theform of cream crystals melting at 210° C.

The 5-(pyridin-3-yl)-2,3-dihydro-1H-pyrrolizine-7-carbonitrile can beprepared in the following manner:

A suspension of N-nicotinoyl-L-proline (44 g) in a mixture of2-chloroacrylonitrile (160 cc) and acetic anhydride (200 cc) is heatedgradually to 90° C. After the reactants have dissolved in the reactionmedium, precipitation is observed, giving rise to a suspension. Theheating of the suspension is continuad for 3 hours 30 minutes at atemperature of the order of 90° C. After cooling at a temperature of theorder of 4° C. for 1 hour, the crystals which have appeared are filteredoff, washed twice with acetic anhydride (50 cc in total) and 3 times inacetone (300 cc in total) and dried under reduced pressure (20 mm Hg;2.7 kPa) at a temperature of the order of 20° C., in the presence ofpotassium hydroxide pellets. The product thus obtained is taken up in a1 N aqueous solution of sodium hydroxide (500 cc). The oil which hasappeared is dissolved in ethyl acetate (250 cc). The organic phase isseparated off by decantation and the aqueous phase is extracted 3 timeswith ethyl acetate (750 cc in total). The organic extracts are combined,washed 3 times with distilled water (750 cc in total), dried overanhydrous potassium carbonate, treated with decolourising charcoal (1 g)and filtered, and the filtrate is concentrated to dryness under reducedpressure (20 mm Hg; 2.7 kPa) at a temperature of the order of 60° C.This gives a crude product (25.2 g). This product is chromatographed ona column of diameter 4 cm, containing silica (0.063-0.2 mm) (250 g),elution being carried out with ethyl acetate and 400 cc fractions beingcollected. The first two fractions are discarded and the next threefractions are combined and concentrated to dryness under reducedpressure (20 mm Hg; 2.7 kPa) at a temperature of the order of 60° C.This gives a product (21 g). This product is dissolved in boilingethanol (100 cc). The solution obtained is cooled at a temperature ofthe order of 4° C. for 1 hour. The crystals which have appeared arefiltered off and washed 3 times with ethanol cooled to a temperature ofthe order of 4° C. (30 cc in total) and then 3 times with isopropylether (150 cc in total). This gives5-(pyridin-3-yl)-2,3dihydro-1H-pyrrolizine-7-carbonitrile (16.1 g) inthe form of cream crystals melting at 112° C.

The N-nicotinoyl-L-proline can be prepared according to F. COUSTOU andB. BELLEGARDE, West German Patent No. 2,537,590.

EXAMPLE 6

A solution of 2-diethylaminoethylamine (13.9 g) in methylene chloride(50 cc) is added in the course of 20 minutes, at a temperature of theorder of 20° C., to a suspension of7-chloroformyl-5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazolehydrochloride (12 g) in methylene chloride (200 cc). The solutionobtained is stirred for 16 hours at a temperature of the order of 20° C.A product precipitates. Methylene chloride (250 cc) and a 2 N aqueoussolution of sodium hydroxide (100 cc) are then added; the organic phaseis separated off by decantation, washed with a 2 N aqueous solution ofsodium hydroxide (100 cc) and then 3 times with distilled water (600 ccin total), dried over anhydrous potassium carbonate, treated withdecolourising charcoal (0.5 g) and filtered, and the filtrate isconcentrated to dryness under reduced pressure (20 mm Hg; 2.7 kPa) at atemperature of the order of 60° C. This gives a crude product (12 g).This product is dissolved in boiling acetonitrile (60 cc). The solutionobtained is treated with decolourising charcoal (0.5 g) and filteredhot; the filtrate is cooled at a temperature of the order of 4° C. for 2hours. The crystals which have appeared are filtered off, washed twicewith acetonitrile cooled to a temperature of the order of 4° C. (20 ccin total) and then 3 times with isopropyl ether (150 cc in total) anddried under reduced pressure (20 mm Hg; 2.7 kPa) at a temperature of theorder of 20° C., in the presence of potassium hydroxide pellets. ThisgivesN-(2-diethylaminoethyl)-5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazole-7-carboxamide(6.4 g) in the form of light beige crystals melting at 106° C.

The 7-chloroformyl-5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazolehydrochloride is prepared as in Example 3.

EXAMPLE 7

Mercuric chloride (10.9 g) is added in the course of 10 minutes, at atemperature of between 20° and 30° C., to a suspension of5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazole-7-carbothioamide (10.4 g)and hydroxylamine hydrochloride (8.4 g) in pyridine (100 cc). Thesuspension obtained is stirred at a temperature of the order of 20° C.for 48 hours and is then poured into distilled water (1,000 cc). Theprecipitate is filtered off, washed 3 times with distilled water (300 ccin total) and extracted continuously for 4 hours with boiling methanol(750 cc) using a Soxhlet extractor. This gives a product (8 g). Thisproduct is dissolved in a 0.5 N aqueous solution of hydrochloric acid(130 cc). The solution obtained is treated with decolourising charcoal(0.5 g) and filtered, and the filtrate is diluted with distilled water(150 cc) and brought to a pH of the order of 10 by adding a 5 N aqueoussolution of sodium hydroxide. The crystals which have appeared arefiltered off, washed 3 times with distilled water (150 cc in total),twice with ethanol (50 cc in total) and then with diethyl ether (50 cc)and dried under reduced pressure (20 mm Hg; 2.7 kPa) at a temperature ofthe order of 20° C., in the presence of potassium hydroxide pellets.This gives a crude product (5.8 g) melting at 200° C. This product ischromatographed on a column of diameter 2.5 cm, containing silica(0.063 - 0.2 mm) (60 g), 100 cc fractions being collected. The first 3fractions from elution with pure methylene chloride, the next 2fractions from elution with a mixture of methylene chloride and methanol(98/2 by volume), the next 2 fractions from elution with a mixture ofmethylene chloride and methanol (96/4 by volume) and the next 2fractions from elution with a mixture of methylene chloride and methanol(94/6 by volume) are discarded. The next 7 fractions from elution with amixture of methylene chloride and methanol (90/10 by volume) and thenext 4 fractions from elution with a mixture of methylene chloride andmethanol (80/20 by volume) are combined and concentrated to drynessunder reduced pressure (20 mm Hg; 2.7 kPa) at a temperature of the orderof 40° C. This gives a product (5 g) melting at 208° C. This product isdissolved in a mixture of butan-1-ol (35 cc) and dimethylformamide (25cc) at a temperature of the order of 115° C. The solution obtained istreated with decolourising charcoal (0.5 g) and filtered; the filtrateis cooled at a temperature of the order of 4° C. for 2 hours. Thecrystals which have appeared are filtered off, washed twice withbutan-1-ol (20 cc in total), twice with ethanol (50 cc in total) andthen 3 times with isopropyl ether (150 cc in total) and dried underreduced pressure (20 mm Hg; 2.7 kPa) at a temperature of the order of20° C., in the presence of potassium hydroxide pellets. This gives5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazole-7-carboxamide-oxime (3.7g) in the form of cream crystals melting at 214° C.

The 5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazole-7-carbothioamide isprepared as in Example 2.

EXAMPLE 8

A suspension of S-methyl5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazole-7-thiocarboximidatehydroiodide (20.2 g) and N,N-dimethylhydrazine (3.4 g) in ethanol (100cc) is heated at the boil for 5 hours 30 minutes and then filtered hot.After cooling to a temperature of the order of 20° C., diethyl ether(350 cc) is added to the filtrate. The suspension obtained is stirred ata temperature of the order of 20° C. for 30 minutes. The crystals whichhave appeared are filtered off, washed twice with a mixture of ethanoland diethyl ether (50/50 by volume) (100 cc in total) and dried underreduced pressure (20 mm Hg; 2.7 kPa) at a temperature of the order of20° C., in the presence of potassium hydroxide pellets. The productobtained is suspended in a mixture of water (300 cc) and ethyl acetate(300 cc). A 10 N aqueous solution of sodium hydroxide (100 cc) is addedto this suspension. The organic phase is separated off by decantationand the aqueous phase is extracted twice with ethyl acetate (300 cc intotal). The organic extracts are combined, washed 3 times with distilledwater (300 cc in total), dried over anhydrous magnesium sulphate,treated with decolourising charcoal (0.5 g) and filtered, and thefiltrate is concentrated to dryness under reduced pressure (20 mm Hg;2.7 kPa) at a temperature of the order of 50° C. This gives a crudeproduct (9.3 g) melting at 168° C. This product is dissolved in boilingethanol (100 cc). The solution obtained is treated with decolourisingcharcoal (0.5 g) and filtered hot; the filtrate is cooled at atemperature of the order of 4° C. for 1 hour. The crystals which haveappeared are filtered off, washed 3 times with ethanol cooled to atemperature of the order of 4° C. (30 cc in total) and 3 times withisopropyl ether (60 cc in total) and dried under reduced pressure (20 mmHg; 2.7 kPa) at a temperature of the order of 20° C., in the presence ofpotassium hydroxide pellets. This gives5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazole-7-carboxamide-dimethylhydrazone(4.95 g) in the form of cream crystals melting at 170° C.

The S-methyl5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazole-7-thiocarboximidatehydroiodide can be prepared in the following manner:

A suspension of5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazole-7-carbothioamide (81.3 g)and methyl iodide (49 g) in a mixture of acetone (3,110 cc) anddimethylformamide (1,550 cc) is stirred at a temperature of the order of20° C. for 3 days. The crystals which have appeared are filtered off,washed 3 times with acetone (1,500 cc in total) and then twice withdiethyl ether (500 cc in total) and dried under reduced pressure (20 mmHg; 2.7 kPa) at a temperature of the order of 20° C., in the presence ofpotassium hydroxide pellets. This gives S-methyl5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazole-7-thiocarboximidatehydroiodide (113 g) in the form of yellow crystals melting at 262° C.

The 5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazole-7-carbothioamide canbe prepared as in Example 2.

EXAMPLE 9

Triethylamine (26.5 g) is added in the course of 20 minutes, at atemperature of between 16 and 27° C., to a suspension of7-chloroformyl-5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazolehydrochloride (15.7 g) and hydroxylamine hydrochloride (10.9 g) inmethylene chloride (390 cc). The solution obtained is stirred for 16hours at a temperature of the order of 20° C. The crystals which haveappeared are filtered off, washed 3 times with methylene chloride (150cc in total) and dried under reduced pressure (20 mm Hg; 2.7 kPa) at atemperature of the order of 20° C., in the presence of potassiumhydroxide pellets. The crystals obtained are suspended in distilledwater (250 cc) at a temperature of the order of 20° C. for 70 minutes,with stirring. The crystals are filtered off, washed 3 times withdistilled water (150 cc in total), 3 times with acetone (150 cc intotal) and 3 times with diethyl ether (150 cc in total) and dried underreduced pressure (20 mm Hg; 2.7 kPa) at a temperature of the order of20° C., in the presence of potassium hydroxide pellets. This gives acrude product (11.6 g) melting at 195° C. This product, combined with aproduct originating from an earlier operation (2 g), is dissolved inboiling butan-1 -ol (500 cc). Decolourising charcoal (0.5 g) is added tothe solution obtained and the mixture is filterad; the filtrate iscooled at a temperature of the order of 4° C. for 1 hour. The crystalswhich have appeared are filtered off, washed twice with butan-1-ol (50cc in total), 3 times with ethanol (150 cc in total) and then 3 timeswith diethyl ether (150 cc in total) and dried under reduced pressure(20 mm Hg; 2.7 kPa) at a temperature of the order of 20° C., in thepresence of potassium hydroxide pellets. This gives5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazole-7-carbohydroxamic acid(8.4 g) in the form of ochre-coloured crystals melting at 210° C.

The 7-chloroformyl-5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazolehydrochloride is prepared as in Example 3.

EXAMPLE 10

A suspension of S-methyl5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazole-7-thiocarboximidatehydroiodide (20.2 g), piperidine (8.6 g) and acetic acid (10.5 g) inchloroform (500 cc) is stirred at 20° C. for 3 days. A 2.8 N aqueoussolution of sodium hydroxide (360 cc) and chloroform (200 cc) are thenadded to the suspension. The organic phase is separated off bydecantation and the aqueous phase is extracted twice with chloroform(1,000 cc in total). The organic extracts are combined, washed 3 timeswith distilled water (750 cc in total), dried over anhydrous magnesiumsulphate, treated with decolourising charcoal (0.5 g) and filtered, andthe filtrate is concentrated to dryness under reduced pressure (20 mmHg; 2.7 kPa) at a temperature of the order of 60° C. This gives aproduct (15 g), which is taken up in boiling ethyl acetate (200 cc).After cooling to a temperature of the order of 20° C., the crystalswhich have appeared are filtered off and the filtrate is concentrated todryness under reduced pressure (20 mm Hg; 2.7 kPa) at a temperature ofthe order of 60° C. This gives a product (14.1 g). This product isdissolved in ethanol (130 cc) and the solution obtained is treated witha 4.7 N ethanolic solution of hydrogen chloride (19.3 cc) and is thencooled at a temperature of the order of 4° C. for 1 hour. The crystalswhich have appeared are filtered off, washed 3 times with ethanol (75 ccin total) and 3 times with diethyl ether (150 cc in total) and driedunder reduced pressure (20 mm Hg; 2.7 kPa) at a temperature of the orderof 20° C., in the presence of potassium hydroxide pellets. This gives acrude product (13.7 g) in the form of the dihydrochloride, melting at264° C. This product is combined with a product prepared in a previousoperation (2.4 g) and is dissolved in distilled water (200 cc). A 1 Naqueous solution of sodium hydroxide (84 cc) and ethyl acetate (250 cc)are added to the solution obtained. The organic phase is separated offby decantation and the aqueous phase is extracted twice with ethylacetate (200 cc in total). The organic extracts are combined, dried overanhydrous potassium carbonate, treated with decolourising charcoal (0.5g) and filtered, and the filtrate is concentrated to dryness underreduced pressure (20 mm Hg; 2.7 kPa) at a temperature of the order of60° C. This gives a product (13 g). This product is chromatographed on acolumn of diameter 2.4 cm, containing silica (0.063-0.2 mm) (65 g),elution being carried out with mixtures of acetonitrile and aqueousammonia (d=0.92) and 100 cc fractions being collected. The first 2fractions from elution with a mixture of acetonitrile and aqueousammonia (95/5 by volume) are discarded. The third fraction from elutionwith a mixture of acetonitrile and aqueous ammonia (95/5 by volume) andthe next 9 fractions from elution with a mixture of acetonitrile andaqueous ammonia (90/10 by volume) are combined and concentrated todryness under reduced pressure (20 mm Hg; 2.7 kPa) at a temperature ofthe order of 40° C. This gives a product (11.3 g). This product ischromatographed again on a column of diameter 6 cm, containing silica(0.04-0.063 mm) (480 g). Elution is carried out with a mixture ofmethylene chloride, methanol and 20% strength aqueous ammonia (12/6/1 byvolume) under a pressure of 0.5 bar (51 kPa), 100 cc fractions beingcollected. The first 7 fractions are discarded and the next 14 fractionsare combined and concentrated to dryness under reduced pressure (20 mmHg; 2.7 kPa) at a temperature of the order of 40° C. This gives aproduct (9.6 g). This product is taken up in boiling ethyl acetate (350cc) and the suspension obtained is filtered hot; the filtrate is thencooled to a temperature of the order of 20° C. and concentrated todryness under reduced pressure (20 mm Hg; 2.7 kPa) at a temperature ofthe order of 60° C. This gives a product (9.1 g). This product isdissolved in ethanol (100 cc). The solution obtained is treated with 4.7N ethanolic solution of hydrogen chloride (12.4 cc) and is cooled at atemperature of the order of 4° C. for 2 hours. The crystals which haveappeared are filtered off, washed twice with ethanol cooled at atemperature of the order of 4° C. (50 cc in total) and then 3 times withdiethyl ether (150 cc in total) and dried under reduced pressure (20 mmHg; 2.7 kPa) at a temperature of the order of 20° C., in the presence ofpotassium hydroxide pellets. This gives a product (9.7 g). This productis dissolved in a boiling mixture of ethanol (175 cc) and distilledwater (10 cc). The solution obtained is treated with decolourisingcharcoal (0.5 g) and filtered hot; the filtrate is cooled at atemperature of the order of 4° C. for 3 hours. The crystals which haveappeared are filtered off, washed 3 times with ethanol (30 cc in total)and 3 times with diethyl ether (75 cc in total) and dried under reducedpressure (20 mm Hg; 2.7 kPa) at a temperature of the order of 20° C., inthe presence of potassium hydroxide pellets. This gives7-piperidinocarbonimidoyl-5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazoledihydrochloride (4.5 g) in the form of pale yellow crystals melting at284° C.

The S-methyl5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazole-7-thiocarboximidatehydroiodide is prepared as in Example 8.

EXAMPLE 11

A suspension of S-methyl5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazole-7-thiocarboximidatehydroiodide (52.4 g), ammonium acetate (20 g) and acetic acid (27.3 g)in chloroform (1,300 cc) is heated at the boil for 20 hours, withstirring. The suspension is then cooled to a temperature of the order of20° C. and the crystals are filtered off, washed 3 times with chloroform(450 cc in total) and 3 times with diethyl ether (450 cc in total) anddried under reduced pressure (20 mm Hg; 2.7 kPa) at a temperature of theorder of 20° C., in the presence of potassium hydroxide pellets. Thisgives a product (52 g). This product (49.5 g) is dissolved in boilingdistilled water (1,800 cc). The solution obtained is cooled to atemperature of the order of 50° C. and treated with ethyl acetate (600cc) and a 10 N aqueous solution of sodium hydroxide (250 cc). Afterstirring for 10 minutes at a temperature of the order of 50° C. and thencooling to a temperature of the order of 20° C., followed bydecantation, the organic phase is discarded and the aqueous phase isextracted twice with ethyl acetate (1,100 cc). The aqueous phase istreated with a mixture of ethyl acetate (1,100 cc) and a 10 N aqueoussolution of sodium hydroxide (2,800 cc) the temperature being kept atabout 25° C. The organic phase is separated off by decantation and theaqueous phase is extracted twice with ethyl acetate (1,200 cc in total).The organic extracts are combined, washed 3 times with distilled water(750 cc in total), dried over anhydrous magnesium sulphate, treated withdecolourising charcoal (0.5 g) and filtered, and the filtrate isconcentrated to dryness under reduced pressure (20 mm Hg; 2.7 kPa) at atemperature of the order of 60° C. This gives a product (14.5 g). Thisproduct is dissolved in boiling methanol (200 cc). The solution obtainedis treated with decolourising charcoal (0.5 g) and filtered; thefiltrate is cooled at a temtemperature of the order of 4° C. for 3 days.The crystals which have appeared are filtered off, washed twice withmethanol cooled to a temperature of the order of 4° C. (20 cc) and then3 times with diethyl ether (75 cc in total) and dried under reducedpressure (20 mm Hg; 2.7 kPa) at a temperature of the order of 20° C., inthe presence of potassium hydroxide pellets. This gives a product (8.3g). This product is dissolved in distilled water (150 cc). The solutionobtained is treated with a 10 N aqueous solution of sodium hydroxide(150 cc). The suspension obtained is stirred at a temperature of theorder of 20° C. for 3 hours. The crystals which have appeared arefiltered off, washed 5 times with distilled water (170 cc in total) anddried under reduced pressure (20 mm Hg; 2.7 kPa) at a temperature of theorder of 20° C., in the presence of potassium hydroxide pellets. Thisgives a crude product (5.5 g). This product is combined with a productprepared in the same manner in a previous operation (4.3 g) anddissolved in boiling ethanol (180 cc). The solution obtained is treatedwith decolourising charcoal (0.5 g) and filtered; the filtrate is cooledat a temperature of the order of 4° C. for 2 hours. The crystals whichhave appeared are filtered off, washed 3 times with ethanol cooled to atemperature of the order of 4° C. (30 cc in total) and 3 times withdiethyl ether (75 cc in total) and dried under reduced pressure (20 mmHg; 2.7 kPa) at a temperature of the order of 20° C., in the presence ofpotassium hydroxide pellets. This gives5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazole-7-carboxamidine (6.5 g) inthe form of cream crystals melting at 200° C.

The S-methyl5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazole-7-thiocarboximidatehydroiodide is prepared as in Example 8.

EXAMPLE 12

A suspension of6-(pyridin-3-yl)-3,4-dihydro-1H-pyrrolo[2,1-c]-1,4-thiazine-8-carbonitrile(4.9 g) and powdered potassium hydroxide (6.7 g) in tert.-butyl alcohol(50 cc) is heated at the boil for 1 hour 15 minutes. The solvent is thenevaporated off under reduced pressure (20 mm Hg; 2.7 kPa) at atemperature of the order of 60° C. and the residue is then suspended indistilled water (150 cc). The crystals which have appeared are filteredoff, washed 3 times with distilled water (150 cc in total) and driedunder reduced pressure (20 mm Hg; 2.7 kPa) at a temperature of the orderof 20° C. This gives a crude product (5.2 g) melting at 186° C. Thisproduct is combined with a product prepared in the same way in previousoperations (4.5 g) and is dissolved in boiling ethanol (250 cc). Thesolution obtained is treated with decolourising charcoal (0.5 g) andthen filtered hot; the filtrate is cooled at a temperature of the 4° C.for 2 hours. The crystals which have appeared are filtered off, washedtwice with ethanol cooled to a temperature of the order of 4° C. (50 ccin total) and then 3 times with diethyl ether (75 cc in total) and driedunder reduced pressure (20 mm Hg; 2.7 kPa) at a temperature of the orderof 20° C., in the presence of potassium hydroxide pellets. This gives6-(pyridin-3-yl)-3,4-dihydro-1H-pyrrolo[2,1-c]-1,4-thiazine-8-carboxamide(7.1 g) in the form of yellow crystals melting at 192° C.

The6-(pyridin-3-yl)-3,4-dihydro-1H-pyrrolo[2,1-c]-1,4-thiazine-8-carbonitrilecan be prepared in the following manner:

A suspension of N-nicotinoyl-1,4-thiazine-3-carboxylic acid (27.9 g) ina mixture of 2-chloroacrylonitrile (89 cc) and acetic anhydride (117 cc)is heated gradually. When the temperature reaches 70° C., thetemperature is seen to rise to 90° C. and the suspended materialdissolves, this being followed, after 5 minutes at this temperature, bycrystallisation, producing a suspension. Heating is continued at atemperature of the order of 90° C. for 2 hours and the reaction mixtureis then cooled to a temperature of the order of 20° C. The crystals arefiltered off, washed 3 times with acetic anhydride (75 cc in total) andthen 3 times with acetone (150 cc in total) and dried under reducedpressure (20 mm Hg; 2.7 kPa) at a temperature of the order of 20° C., inthe presence of potassium hydroxide pellets. This gives a product (6.3g). This product is suspended in distilled water (100 cc). Thesuspension obtained is treated with a 5 N aqueous solution of sodiumhydroxide (50 cc) and then extracted 3 times with ethyl acetate (300 ccin total). The organic extracts are combined, washed 3 times withdistilled water (150 cc in total), dried over anhydrous magnesiumsulphate, treated with decolourising charcoal (0.5 g) and filtered, andthe filtrate is concentrated to dryness under reduced pressure (20 mmHg; 2.7 kPa) at a temperature of the order of 60° C. This gives6-(pyridin-3-yl)-3,4-dihydro-1H-pyrrolo[2,1-c]-1,4-thiazine-8-carbonitrile(5 g) in the form of light orange crystals melting at 150° C.

The N-nicotinoyl-1,4-thiazine-3-carboxylic acid can be prepared in thefollowing manner:

A solution of ethyl N-nicotinoyl-1,4-thiazine-3-carboxylate (2.8 g) in amixture of ethanol (25 cc) and a 2 N aqueous solution of sodiumhydroxide (10 cc) is stirred at a temperature of the order of 20° C. for3 hours. The solvent is then evaporated off under reduced pressure (20mm Hg; 2.7 kPa) at a temperature of the order of 50° C. The productobtained is dissolved in distilled water (50 cc) and purified by passingthis solution over DOWEX 50WX-2 resin (50-100 mesh) (30 g) contained ina column of diameter of 1.6 cm. The first fraction from elution withdistilled water, the second fraction from elution with methanol and thethird fraction from elution with distilled water are discarded, as arealso the next 2 fractions from elution with a 2% strength (v/v) aqueoussolution of pyridine. The next 2 fractions from elution with a 2%strength (v/v) aqueous solution of pyridine are combined andconcentrated to dryness under reduced pressure (20 mm Hg; 2.7 kPa) at atemperature of the order of 50° C. This gives a crude product (2.3 g).This product is dissolved in boiling methanol (50 cc) and the solutionobtained is cooled at a temperature of the order of 4° C. for 1 hour.The crystals which have appeared are filtered off, washed twice withmethanol (100 cc in total) and then 3 times with isopropyl ether (45 ccin total) and dried under reduced pressure (20 mm Hg; 2.7 kPa) at atemperature of the order of 20° C., in the presence of potassiumhydroxide pellets. This gives N-nicotinoyl-1,4-thiazine-3-carboxylicacid (1.5 g) in the form of white crystals melting at 212° C.

The ethyl N-nicotinoyl-1,4-thiazine-3-carboxylate can be obtained in thefollowing manner.

Nicotinoyl chloride hydrochloriJe (8.9 g) is added in the course of 25minutes, at a temperature of between 24° C. and 38° C., to a solution ofethyl 1,4-thiazine-3-carboxylate (8.8 g) and triethylamine (10.1 g) inchloroform (125 cc). The solution obtained is stirred for 3 hours at atemperature of the order of 20° C. and triethylamine (10.1 g) is thenadded, followed in the course of 15 minutes, at a temperature of between24° C. and 36° C., by nicotinoyl chloride hydrochloride (8.9 g). Thesolution obtained is stirred for 16 hours at a temperature of the orderof 20° C. and then for 2 hours at the boil. The reaction mixture iscooled to a temperature of the order of 20° C. and treated with amixture of chloroform (250 cc) and distilled water (100 cc). The organicphase is separated off by decantation, washed with distilled water (100cc) and then twice with a 2 N aqueous solution of sodium hydroxide (300cc in total) and twice with distilled water (200 cc in total), driedover anhydrous potassium carbonate, treated with decolourising charcoal(0.5 g) and filtered, and the filtrate is concentrated to dryness underreduced pressure (20 mm Hg; 2.7 kPa) at a temperature of the order of60° C. This gives a crude product (17.5 g). This product ischromatographed on a column of diameter 6 cm, containing silica(0.04-0.063 mm) (480 g). Elution is carried out with a mixture of ethylacetate and methanol (98/2 by volume) under a pressure of 0.5 bar (51kPa), 100 cc fractions being collected. The first 14 fractions arediscarded; the next 9 fractions are combined and concentrated to drynessunder reduced pressure (20 mm Hg; 2.7 kPa) at a temperature of the orderof 60° C. This gives ethyl N-nicotinoyl-1,4-thiazine-3-carboxylate (9.6g) in the form of a yellow oil.

[Rf=0.35; chromatography on a thin layer of silica gel; solvent: ethylacetate/methanol (98/2 by volume)].

The ethyl 1,4-thiazine-3-carboxylate can be obtained according to B.BELLEAU, J. Med. Pharm. Chem. 2, 553 (1960).

EXAMPLE 13

A suspension ofN-nicotinoyl-3,4,5,6-tetrahydro-2H-1,3-thiazine-4-carboxylic acid (21.5g) and 2-chloroacrylamide (32 g) in acetic anhydride (250 cc) is heatedat a temperature of the order of 75° C. for 15 minutes and then at atemperature of the order of 95° C. for 1 hour. The suspension obtainedis then cooled at a temperature of the order of 4° C. for 1 hour and thecrystals are filtered off, washed 3 times with acetic anhydride (15 ccin total) and then 3 times with diethyl ether (45 cc in total) and driedunder reduced pressure (20 mm Hg; 2.7 kPa) at a temperature of the orderof 20° C., in the presence of potassium hydroxide pellets. This gives aproduct (16.1 g). This product is dissolved in distilled water (750 cc)at a temperature.of the order of 45° C. and the solution obtained isthen brought to a pH of the order of 8 by adding sodium bicarbonate. Thesuspension obtained is cooled at a temperature of the order of 4° C. for70 minutes and the crystals are filtered off, washed 3 times withdistilled water (240 cc in total), 3 times with ethanol (10 cc in total)and 3 times with diethyl ether (30 cc in total) and dried under reducedpressure (20 mm Hg; 2.7 kPa) at a temperature of the order of 20° C., inthe presence of potassium hydroxide pellets. This gives a product (12.9g) melting at 220° C. This product, combined with a product originatingfrom a previous operation (1.3 g), is dissolved in boiling ethanol (800cc). The solution obtained is treated with decolourising charcoal (0.5g) and filtered hot; the filtrate is cooled at a temperature of theorder of 4° C. for 1 hour. The crystals which have appeared are filteredoff, washed 3 times with ethanol cooled to a temperature of the order of4° C. (60 cc in total) and then 3 times with diethyl ether (60 cc intotal) and dried under reduced pressure (20 mm Hg; 2.7 kPa) at atemperature of the order of 20° C., in the presence of potassiumhydroxide pellets. This gives6-(pyridin-3-yl)-1,2-dihydro-4H-pyrrolo[1,2-c]-1,3-thiazine-8-carboxamide(12.6 g) in the form of white crystals melting at 220° C.

The 2-chloroacrylamide can be prepared according to S.S. IVANOV and M.M.KOTON, J. Gen. Chem. U.S.S.R., 28, 139 (1958); Chem. Abstr. 52, 12757 d,(1958).

The N-nicotinoyl-3,4,5,6-tetrahydro-2H-1,3-thiazine-4-carboxylic acidcan be prepared in the following manner:

A solution of ethylN-nicotinoyl-3,4,5,6-tetrahydro-2H-1,3-thiazine-4-carboxylate (37.8 g)in a mixture of a 5 N aqueous solution of sodium hydroxide (80 cc) andethanol (80 cc) is stirred at a temperature of the order of 20° C. for16 hours. The solvent is then evaporated off under reduced pressure (20mm Hg; 2.7 kPa) at a temperature of the order of 50° C. The residue isdissolved in distilled water (100 cc) and purified by passing thesolution obtained over DOWEX 50WX-2 resin (50-100 mesh) (630 g)contained in a column of diameter 4.5 cm. Elution is carried out withdistilled water (4,000 cc), then with a mixture of water and methanol(50/50 by volume) (1,000 cc), then with methanol (2,000 cc) and thenwith distilled water (2,000 cc). All the corresponding fractions arediscarded. The next 6 fractions, each of 1,000 cc, from elution with a2% strength (v/v) aqueous solution of pyridine are combined andconcentrated to dryness under reduced pressure (20 mm Hg; 2.7 kPa) at atemperature of the order of 50° C. The residue is taken up in ethanol(150 cc) and the solvent is evaporated off under reduced pressure (20 mmHg; 2.7 kPa) at a temperature of the order of 50° C. This operation isrepeated once. The residue finally collected is dissolved in a boilingmixture of ethanol and water (60/40 by volume) (350 cc). The solutionobtained is treated with decolourising charcoal (0.5 g) and filteredhot; the filtrate is cooled at a temperature of the order of 4° C. for 1hour. The crystals which have appeared are filtered off, washed 3 timeswith a mixture of ethanol and water (60/40 by volume) (60 cc in total)and then 3 times with ethanol (60 cc in total) and dried under reducedpressure (20 mm Hg; 2.7 kPa) at a temperature of the order of 20° C., inthe presence of potassium hydroxide pellets. This givesN-nicotinoyl-3,4,5,6-tetrahydro-2H-1,3-thiazine-4-carboxylic acid (24.2g) in the form of white crystals melting at 214° C.

The ethyl N-nicotinoyl-3,4,5,6-tetrahydro-2H-1,3-thiazine-4-carboxylatecan be prepared in the following manner:

A mixture of triethylamine (75 g) and chloroform (100 cc) is added inthe course of 15 minutes, at a temperature of the order of 20° C., to asuspension of ethyl 3,4,5,6-tetrahydro-2H-1,3-thiazine-4-carboxylatehydrochloride (37.2 g) in chloroform (350 cc). Nicotinoyl chloridehydrochloride (50.4 g) is added to the solution thus obtained in thecourse of 10 minutes, at a temperature of the order of 20° C. Thereaction mixture is heated at a temperature of the order of 65° C. for 1hour 45 minutes and is then stirred at a temperature of the order of 20°C. for 16 hours. The reaction mixture is washed 3 times with distilledwater (600 cc in total) and then 3 times with a saturated aqueoussolution of potassium bicarbonate (600 cc in total), dried overanhydrous magnesium sulphate, treated with decolourising charcoal (0.5g) and filtered, ahd the filtrate is concentrated to dryness underreduced pressure (20 mm Hg; 2.7 kPa) at a temperature of the order of50° C. This gives a product (52 g). This product is chromatographed on acolumn of diameter 5.2 cm, containing silica (0.063-0.2 mm) (520 g), 500cc fractions being collected. The first fraction from elution with amixture of cyclohexane and ethyl acetate (50/50 by volume) is discarded.The next 3 fractions from elution with a mixture of ethyl acetate andcyclohexane (50/50 by volume), the next 2 fractions from elution with amixture of ethyl acetate and cyclohexane (70/30 by volume) and the nextfraction from elution with a mixture of ethyl acetate and cyclohexane(80 20 by volume) are combined and concentrated to dryness under reducedpressure (20 mm Hg; 2.7 kPa) at a temperature of the order of 50° C.This gives ethylN-nicotinoyl-3,4,5,6-tetrahydro-2H-1,3-thiazine-4-carboxylate (37.8 g)in the form of a yellow oil. [Rf=0.33; chromatography on a thin layer ofsilica gel; solvent: ethyl acetate cyclohexane (80/20 by volume)].

The ethyl 3,4,5,6-tetrahydro-2H-1,3-thiazine-4-carboxylate hydrochloridecan be prepared in the following manner:

A suspension of 3,4,5,6-tetrahydro-2H-1,3-thiazine-4-carboxylic acid(47.7 g) in ethanol (650 cc) is saturated for 4 hours, at a temperatureof the order of 20° C., with a stream of dry hydrogen chloride. Thesuspension is stirred for 3 days at a temperature of the order of 20° C.and is then heated at a temperature of the order of 80° C. for 3 hours20 minutes, with stirring. After cooling the solution obtained to atemperature of the order of 4° C., the crystals which have appeared arefiltered off, washed 3 times with ethanol cooled to a temperature of theorder of 4° C. (30 cc in total) and then 3 times with diethyl ether (120cc in total) and dried under reduced pressure (20 mm Hg; 2.7 kPa) at atemperature of the order of 20° C., in the presence of potassiumhydroxide pellets. This gives ethyl3,4,5,6-tetrahydro-2H-1,3-thiazine-4-carboxylate hydrochloride (37.2 g)in the form of white crystals melting at 185° C.

The 3,4,5,6-tetrahydro-2H-1,3-thiazine-4-carboxylic acid can be preparedaccording to J. C. WRISTON Jr. and C. G. MACKENZIE, J. Biol. Chem., 225,607 (1957).

EXAMPLE 14

A suspension of powdered potassium hydroxide (11.2 g) and a mixture (inthe ratio 69/31) of 6-cyano and7-cyano-5-[2-(pyridin-3-yl)-vinyl]-1H,3H-pyrrolo[1,2-c]thiazole (10.2 g)in tert.-butyl alcohol (110 cc) is heated under reflux for one hour. Thesolvent is then evaporated off under reduced pressure (20 mm Hg; 2.7kPa) at a temperature of the order of 50° C. After the addition ofdistilled water (200 cc), the crystals which have appeared are filteredoff, washed four times with distilled water (120 cc in total) and driedunder reduced pressure (20 mm Hg; 2.7 kPa) at a temperature of the orderof 20° C., in the presence of potassium hydroxide pellets. This gives acrude product (11 g). This product is chromatographed on a column ofdiameter of 3.2 cm, containing silica (0.063-0.2 mm) (110 g), 1,000 ccfractions being collected. The first fraction from elution with puremethylene chloride, the second fraction from elution with a mixture ofmethylene chloride and methanol (97.5/2.5 by volume), the third fractionfrom elution with a mixture of methylene chloride and methanol (95/5 byvolume) and the fourth fraction from elution with a mixture of methylenechloride and methanol (92.5/7.5 by volume) are discarded. The fifthfraction from elution with a mixture of methylene chloride and methanol(90/10 by volume) and the sixth fraction from elution with a mixture ofmethylene chloride and methanol (85/15 by volume) are combined andconcentrated to dryness under reduced pressure (20 mm Hg; 2.7 kPa) at atemperature of the order of 40° C. This gives a product (3.7 g) meLtingat 180° C. This product is dissolved in boiling acetonitrile (700 cc).After cooling at a temperature of the order of 4 ° C. for one hour, thecrystals which have appeared are filtered off and dried and reducedpressure (20 mm Hg; 2.7 kPa) at a temperature of the order of 20° C., inthe presence of potassium hydroxide pellets. This gives a product (2.4g), which is combined with a product prepared in the same way in aprevious operation (0.9 g) and chromatographed on a column of diameter2.8 cm, containing silica (0.063-0.2 mm) (35 g), 500 cc fractions beingcollected. The first two fractions from elution with pure methylenechloride and the next two from elution with a mixture of methylenechloride and methanol (97.5/2.5 by volume) are discarded. The fifth andsixth fractions from elution with a mixture of methylene chloride andmethanol (95/5 by volume) and the seventh fraction from elution with amixture of methylene chloride and methanol (90/10 by volume) arecombined and concentrated to dryness under reduced pressure (20 mm Hg;2.7 kPa) at a temperature of the order of 40° C. This gives a product(3.1 g), which is dissolved in boiling acetonitrile (900 cc). Thesolution is treated with decolourising charcoal (0.3 g) and filteredhot. After cooling at a temperature of the order of 4° C. for 2 hours,the crystals which have appeared are filtered off, washed twice withacetonitrile (60 cc in total) and dried under reduced pressure (20 mmHg; 2.7 kPa) at a temperature of the order of 20° C., in the presence ofpotassium hydroxide pellets. This gives5-[2-(pyridin-3-yl)-vinyl]-1H,3H-pyrrolo[1,2-c]thiazole-7-carboxamide(2.1 g) melting at 242° C.

The mixture (69/31) of 6-cyano and7-cyano-5-[2-(pyridin-3-yl)-vinyl]-1H,3H-pyrrolo[2-c]thiazole can beprepared in the following manner:

A suspension of N-[3-(pyridin-3-yl)-acryloyl]thiazolidine-4-carboxylicacid (13.2 g) in a mixture of 2-chloroacrylonitrile (39.6 cc) and aceticanhydride (52 cc) is heated at about 83° C. for 4 hours. After coolingfor 16 hours at a temperature of the order of 4° C., the crystals whichhave appeared are filtered off and washed twice with acetic anhydride(10 cc in total) and three times with acetone (60 cc in total). Theproduct thus obtained is suspended in distilled water (70 cc). Themixture is brought to a pH of the order of 10 by adding a 2N aqueoussolution of sodium hydroxide. After stirring at a temperature of theorder of 20° C. for one hour, the crystals which have appeared arefiltered off, washed three times with distilled water (60 cc in total),twice with acetone (40 cc in total) and twice with diethyl ether (40 ccin total) and dried under reduced pressure (20 mm Hg; 2.7 kPa) at atemperature of the order of 20° C., in the presence of potassiumhydroxide pellets. This gives a mixture of 6-cyano and7-cyano-5-[2-(pyridin-3-yl)-vinyl]-1H,3 H-pyrrolo[1,2-c]thiazole in theform of beige crystals melting at 170° C.

The N-[3-(pyridin-3-yl)-acryloyl]-thiazolidine-4-carboxylic acid can beobtained in the following manner:

3-(Pyridin-3-yl)-acryloyl chloride hydrochloride (34.1 g) is added inthe course of 30 minutes, at a temperature of between 20° C. and 35° C.,to a solution of thiazolidine-4-carboxylic acid (22.5 g) in a mixture oftriethylamine (47 cc) and chloroform (250 cc). The reaction mixture isheated under reflux for 16 hours and then concentrated to dryness underreduced pressure (20 mm Hg; 2.7 kPa). The residue obtained, treated withdistilled water (500 cc), is heated to the reflux temperature. After theaddition of decolourising charcoal (1 g), the mixture is filtered hotand the filtrate is cooled at 4° C. for 16 hours. The crystals whichhave appeared are filtered off, washed twice with distilled water (100cc in total) and once with ethanol (30 cc) and then dried under reducedpressure (20 mm Hg; 2.7 kPa) at a temperature of the order of 20° C., inthe presence of potassium hydroxide pellets. This gives a crude product(21.1 g) melting at 173° C. This product is dissolved in boiling ethanol(400 cc). The solution obtained is treated with decolourising charcoal(1 g) and filtered hot. The filtrate is cooled at a temperature of theorder of 4° C. for 16 hours. The crystals which have appeared arefiltered off, washed twice with ethanol (40 cc) in total and dried underreduced pressure (20 mm Hg; 2.7 kPa) at a temperature of the order of20° C., in the presence of potassium hydroxide pellets. This givesN-[3-(pyridin-3-yl)-acryloyl]-thiazo[idine-4-carboxylic acid 13.5 g)melting at 176° C.

The 3-(pyridin-3-yl)-acryloyl chloride hydrochloride can be obtained inthe following manner:

Thionyl chloride (200 cc) is added in the course of 15 minutes to3-(pyridin-3-yl)-acrylic acid (50 g). The reaction mixture is thenheated under reflux for 5 hours. The excess thionyl chloride isdistilled and the reaction mixture is then concentrated to dryness afterthe addition of anhydrous cyclohexane (300 cc). This last operation isrepeated once. The residue obtained is treated with chloroform (200 cc)and the mixture is heated under reflux for 15 minutes. After cooling,the crystals are filtered off, washed once with chloroform (50 cc) andtwice with hexane (200 cc in total) and then dried under reducedpressure (20 mm Hg; 2.7 kPa) at a temperature of the order of 20° C., inthe presence of potassium hydroxide pellets. This gives3-(pyridin-3-yl)acryloyl chloride hydrochloride (55 g) melting at 187°C.

The 3-(pyridin-3-yl)-acrylic acid can be prepared according to L.PANNIZZON, Helv. Chim. Acta, 24, 24E (1941).

EXAMPLE 15

A solution of morpholine (10.45 g) in methylene chloride (50 cc) isadded in the course of 15 minutes, at a temperature of between 24° C.and 33° C., to a suspension of7-chloroformyl-5-(pyridin-3-yl)-1H,3H-pyrrolo[1, 2-c]thiazolehydrochloride (12 g) in methylene chloride (200 cc). The solutionobtained is stirred at a temperature of the order of 20° C. for 16 hoursand is then diluted with methylene chloride (250 cc), washed twice withdistilled water (400 cc in total), once with a 2N aqueous solution ofsodium hydroxide (200 cc) and then twice with distilled water (400 cc intotal), dried over anhydrous magnesium sulphate, treated withdecolourising charcoal (0.5 g) and filtered, and the filtrate isconcentrated to dryness under reduced pressure (20 mm Hg; 2.7 kPa) at atemperature of the order of 60° C. This gives a crude product (12.7 g).The product is dissolved in boiling acetonitrile (125 cc). The solutionobtained is treated with decolourising charcoal (0.5 g) and filteredhot. The filtrate is cooled at a temperature of the order of 4° C. for 2hours. The crystals which have appeared are filtered off, washed twicewith acetonitrile cooled to a temperature of the order of 4° C. (10 ccin total) and 3 times with isopropyl ether (75 cc in total) and thendried under reduced pressure (20 mm Hg; 2.7 kPa) at a temperature of theorder of 20° C., in the presence of potassium hydroxide pellets. Thisgives 7-morpholinocarbonyl-5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazole(7.5 g) in the form of beige crystals melting at 150° C.

The 7-chloroformyl-5-(pyridin-3-yl)-1H,3H-pyrrolo [1,2-c]thiazolehydrochloride is prepared as in Example 3.

EXAMPLE 16

A solution of 7-chloroformyl-5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazole hydrochloride (30 g) and triethylamine (20.2g) in m.thylene chloride (500 cc) is added in the course of 25 minutesat a temperature of between 24° C. and 32° C., to a solution ofanhydrous piperazine (26.1 g) in methylene chloride (500 cc). Thesuspension obtained is stirred at a temperature of the order of 20° C.for 16 hours and is then diluted with methylene chloride (600 cc) andwashed twice with a 2N aqueous solution of sodium hydroxide (600 cc intotal). The organic phase is decanted, washed 3 times with distilledwater (1,550 cc in total), dried over anhydrous magnesium sulphate,treated with decolourising charcoal (1 g) and filtered, and the filtrateis concentrated to dryness under reduced pressure (20 mm Hg; 2.7 kPa) ata temperature of the order of 60° C. This gives a product (25.4 g). Thisproduct is dissolved in boiling butan-1-ol (160 cc). The solutionobtained is treated with decolourising charcoal (0.5 g) and filteredhot. The filtrate is cooled at a temperature of the order of 4° C. for16 hours. The crystals which have appeared are filtered off and thefiltrate is concentrated to dryness under reduced pressure (20 mm Hg;2.7 kPa) at a temperature of the order of 70° C. This gives a product(21 g), which is chromatographed on a column of diameter of 3.8 cm,containing silica (0.063-0.2 mm) (210 g). Elution is carried out withmixtures of methylene chloride and methanol, 300 cc fractions beingcollected. The first 7 fractions from elution with a mixture ofmethylene chloride and methanol (95/5 by volume) are discarded; the next3 fractions from elution with a mixture of methylene chloride andmethanol (95/5 by volume), the next 7 fractions from elution with amixture of methylene chloride and methanol (90/10 by volume) and thenext 8 fractions from elution with a mixture of methylene chloride andmethanol (85/15 by volume) are combined and concentrated to drynessunder reduced pressure (20 mm Hg; 2.7 kPa) at a temperature of the orderof 60° C. This gives a product (12.2 g). This product is suspended indistilled water (50 cc) and the suspension obtained is treated with 5Naqueous solution of sodium hydroxide (100 cc) and extracted 3 times withmethylene chloride (750 cc in total). The organic extracts are combined,washed twice with distilled water (200 cc in total), dried overanhydrous magnesium sulphate, treated with decolourising charcoal (0.5g) and filtered, and the filtrate is concentrated to dryness underreduced pressure (20 mm Hg; 2.7 kPa) at a temperature of the order of60° C. This gives a product (11 g). This product is taken up in boilingmethanol (30 cc). The suspension obtained is filtered hot in thepresence of decolourising charcoal (0.5 g) and the filtrate is cooled ata temperature of the order of 4° C. for 3 hours. The crystals which haveappeared are filtered off, washed twice with methanol cooled to atemperature of the order of 4° C. (10 cc in total) and 3 times withdiethyl ether (75 cc in total) and then dried under reduced pressure (20mm Hg; 2.7 kPa) at a temperature of the order of 20° C., in the presenceof potassium hydroxide pellets. This gives a product (5.9 g) melting at252° C. The mother liquors are concentrated to dryness under reducedpressure (20 mm Hg; 2.7 kPa) at a temperature of the order of 60° C.This gives a product (2.8 g), which is taken up in ethanol (25 cc). Thesuspension obtained is heated at the boil for 5 minutes and then cooledto a temperature of the order of 20° C. The crystals are filtered off,washed twice with ethanol (10 cc in total) and dried under reducedpressure (20 mm Hg; 2.7 kPa) at a temperature of the order of 20° C., inthe presence of potassium hydroxide pellets. This gives a product (0.3g) melting at 262° C. The filtrate is poured into a 0.64N ethanolicsolution of hydrogen chloride (28 cc). The crystals which have appearedare filtered off, washed twice with ethanol (20 cc in total) and 3 timeswith isopropyl ether (75 cc in total) and then dried under reducedpressure (20 mm Hg; 2.7 kPa) at a temperature of the order of 20° C., inthe presence of potassium hydroxide pellets. This gives a crude product(2.5 g) melting at 260° C. This product, combined with the productsobtained previously (0.3 g and 5.9 g), is suspended in a 5.35N ethanolicsolution of hydrogen chloride (600 cc). After stirring for 35 minutes ata temperature of the order of 20° C., dissolution is observed, followedby crystallisation 10 minutes later. The suspension obtained is stirredat a temperature of the order of 20° C. for 16 hours. The crystals arefiltered off, washed 3 times with ethanol (75 cc in total) and 3 timeswith diethyl ether (75 cc in total) and then dried under reducedpressure (20 mm Hg; 2.7 kPa) at a temperature of the order of 20° C., inthe presence of potassium hydroxide pellets. This gives7-(piperazin-1-yl-carbonyl)-5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazoleas the trihydrochloride monohydrate (6.7 g) in the form of pale yellowcrystals melting at 242° C.

The 5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazole-7-carboxylic acid isprepared as in Example 3.

EXAMPLE 17

A solution of 1-(2-aminoethyl)-4-methylpiperazine (3.7 g) andtriethylamine (5.3 g) in methylene chloride (45 cc) is added in thecourse of 20 minutes, at a temperature of between 21° C. and 31° C., toa suspension of7-chloroformyl-5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazolehydrochloride (7.8 g) in methylene chloride (130 cc). The solutionobtained is stirred at a temperature of the order of 20° C. for 16 hoursand is then diluted with methylene chloride (200 cc), washed 4 timeswith distilled water (800 cc in total), dried over anhydrous magnesiumsulphate, treated with decolourising charcoal (0.5 g) and filtered, andthe filtrate is concentrated to dryness under reduced pressure (20 mmHg; 2.7 kPa) at a temperature of the order of 60° C. This gives aproduct (6.3 g). This product is dissolved in distilled water (150 cc).The solution obtained and the previous wash waters are combined andrendered alkaline by adding a 5N aqueous solution of sodium hydroxide(250 cc). The suspension obtained is extracted 3 times with methylenechloride (750 cc in total). The organic extracts are combined, washed 3times with distilled water (750 cc in total), dried over anhydrousmagnesium sulphate, treated with decolourising charcoal (0.5 g) andfiltered, and the filtrate is concentrated to dryness under reducedpressure (20 mm Hg; 2.7 kPa) at a temperature of the order of 60° C.This gives a crude product (7.6 g). This product is dissolved in ethanol(150 cc) and the solution obtained is added in the course of 15 minutes,at a temperature of the order of 20° C., to a 1.26N ethanolic solutionof hydrogen chloride (65 cc). The suspension obtained is treated withethanol (25 cc) and then stirred at a temperature of the order of 20° C.for 2 hours. The crystals are filtered off, washed 3 times with ethanol(75 cc in total) and 4 times with diethyl ether (100 cc in total) andthen dried under reduced pressure (20 mm Hg; 2.7 kPa) at a temperatureof the order of 20° C., in the presence of potassium hydroxide pellets.This givesN-[2-(4-methylpiperazin-1-yl)-ethyl]-5(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazole-7-carboxamideas the trihydrochloride (7.4 g) in the form of pale yellow crystalsmelting at 260° C.

The 7-chloroformyl-5-(pyridin-3-yl)-1H,3H-pyrrolo [1,2-c]thiazolehydrochloride is prepared as in Example 3.

EXAMPLE 18

7-Chloroformyl-5-(pyridin-3-yl)-1H,3H-pyrrolo[1, 2-c]thiazolehydrochloride (12 g) is added in the course of 35 minutes, at atemperature of between 23° C. and 30° C., to a solution of4-(2-hydroxyethyl)-piperazine (5.3 g) and triethylamine (8.1 g) inmethylene chloride (250 cc). The solution obtained is stirred at atemperature of the order of 20° C. for 16 hours and is then diluted withmethylene chloride (200 cc) and washed 4 times with distilled water (800cc in total), dried over anhydrous magnesium sulphate, treated withdecolourising charcoal (0.5 g) and filtered, and the filtrate isconcentrated to dryness under reduced pressure (20 mm Hg; 2.7 kPa) at atemperature of the order of 60° C. This gives a crude product (14 g).This product is dissolved in boiling ethanol (130 cc). The solutionobtained is treated with decolourising charcoal (0.5 g) and filteredhot. The filtrate is cooled at a temperature of the order of 4° C. for 1hour. The crystals which have appeared are filtered off, washed twicewith ethanol (50 cc in total) and 4 times with isopropyl ether (100 ccin total) and then dried under reduced pressure (20 mm Hg; 2.7 kPa) at atemperature of the order of 20° C., in the presence of potassiumhydroxide pellets. This gives7-[4-(2-hydroxyethyl)-piperazin-1-yl]-carbonyl-5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazole(8.3 g) in the form of cream crystals melting at 140° C.

The 7-chloroformyl-5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazolehydrochloride is prepared as described in Example 3.

EXAMPLE 19

A solution of 1-benzylpiperazine (30.6 g) in methylene chloride (150 cc)is added in the course of 30 minutes, at a temperature of between 24° C.and 31° C., to a suspension of7-chloroformyl-5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazolehydrochloride (15 g) in methylene chloride (300 cc). The solutionobtained is stirred at a temperature of the order of 20° C. for 16 hoursand then diluted with methylene chloride (300 cc), washed 3 times withdistilled water (750 cc in total), dried over anhydrous magnesiumsulphate, treated with decolourising charcoal (0.5 g) and filtered, andthe filtrate is concentrated to dryness under reduced pressure (20 mmHg; 2.7 kPa) at a temperature of the order of 60° C. This gives a crudeproduct (22.7 g). This product is dissolved in boiling acetonitrile (100cc). The solution obtained is treated with decolourising charcoal (0.5g) and filtered hot. The filtrate is cooled at a temperature of theorder of 4° C. for 1 hour. The crystals which have appeared are filteredoff, washed twice with acetonitrile cooled to a temperature of the orderof 4° C. (50 cc in total) and 3 times with diethyl ether (75 cc intotal) and then dried under reduced pressure (20 mm Hg; 2.7 kPa) at atemperature of the order of 20° C., in the presence of potassiumhydroxide pellets. This gives7-[(4-benzylpiperazin-1-yl)-carbonyl]-5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazole (13 g) in the form of cream crystals meltingat 140° C.

The 7-chloroformyl-5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazolehydrochloride is prepared as described in Example 3.

EXAMPLE 20

A solution of 1-[(pyrrolidin-1-yl)-carbonylmethyl]-piperazine (10.2 g)and triethylamine (10.1 g) in methylene chloride (100 cc) is added inthe course of 30 minutes, at a temperature of between 24 and 32° C., toa suspension of7-chloroformyl-5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazolehydrochloride (15 g) in methylene chloride (250 cc). The solutionobtained is stirred at a temperature of the order of 20° C. for 16 hoursand is then diluted with methylene chloride (300 cc), washed 3 timeswith distilled water (900 cc in total), dried over anhydrous magnesiumsulphate, treated with decolourising charcoal (0.5 g) and filtered, andthe filtrate is concentrated to dryness under reduced pressure (20 mmHg; 2.7 kPa) at a temperature of the order of 60° C. This gives a crudeproduct (20.8 g). This product is taken up in acetonitrile (80 cc). Aproduct crystallises. The suspension obtained is heated to the boil andthe solution obtained is then treated with decolourising charcoal (0.5g) and filtered hot. The filtrate is cooled at a temperature of theorder of 4° C. for 16 hours. The crystals which have appeared arefiltered off, washed twice with acetonitrile cooled to a temperature ofthe order of 4° C. (20 cc in total) and 4 times with diethyl ether (200cc in total) and then dried under reduced pressure (20 mm Hg; 2.7 kPa)at a temperature of the order of 0° C., in the presence of potassiumhydroxide pellets. This gives7-[(4-pyrrolidin-1-yl-carbonylmethylpiperazin-1-yl)-carbonyl]-5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazole(13.2 g) in the form of beige crystals melting at 64° C.

The 7-chloroformyl-5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazolehydrochloride is prepared as in Example 3.

EXAMPLE 21

7-Chloroformyl-5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazolehydrochloride (17.5 g) is added in the course of 15 minutes, at atemperature of between 18° and 27° C., to a solution of histamine (12.9g) in methylene chloride (360 cc). The suspension obtained is stirred ata temperature of the order of 20° C. for 16 hours and is then treatedwith a mixture of methylene chloride (360 cc) and water (300 cc). Thecrystals which have appeared are filtered off, washed 3 times withmethylene chloride (30 cc in total), 3 times with distilled water (300cc in total), 3 times with a 2N aqueous solution of sodium hydroxide(300 cc in total) and 3 times with distilled water (300 cc in total) anddissolved in a 2N aqueous solution of hydrochloric acid (100 cc). Thesolutin obtained is treated with decolourising charcoal (0.5 g) andfiltered. The filtrate is brought to a pH of the order of 10 by adding a10N aqueous solution of sodium hydroxide. The crystals which haveappeared are filtered off, washed 3 times with distilled water (150 ccin total) and 3 times with acetone (75 cc in total) and dried underreduced pressure (20 mm Hg; 2.7 kPa) at a temperature of the order of20° C., in the presence of potassium hydroxide pellets. This gives acrude product (11.8 g). This product is dissolved in boiling isopropanol(250 cc). The solution obtained is treated with decolourising charcoal(0.5 g) and filtered hot. The filtrate is cooled at a temperature of the4° C. for 16 hours. The pasty precipitate which has appeared is filteredoff and the filtrate is concentrated to dryness under reduced pressure(20 mm Hg; 2.7 kPa) at a temperature of the order of 60° C. This gives aproduct (8.4 g) melting at 200° C. This product is dissolved in boilingethanol (350 cc). The solution obtained is treated with decolourisingcharcoal (0.5 g) and filtered hot. The filtrate is cooled for 16 hoursat a temperature of the order of 20° C. The crystals which have appearedare filtered off, washed 3 times with ethanol (30 cc in total) and 3times with diethyl ether (75 cc in total) and dried under reducedpressure (20 mm Hg; 2.7 kPa) at a temperature of the order of 20° C., inthe presence of potassium hydroxide pellets. This givesN-[2-(imidazol-4-yl)ethyl]-5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazole-7-carboxamide(5.6 g) in the form of cream crystals melting at 226° C.

The 7-chloroformyl-5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazolehydrochloride is prepared as described in Example 3.

EXAMPLE 22

A suspension of5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazole-7-carbonitrile (3.6 g),ethanolamine (3.8 g) and lithium chloride (0.1 g) is heated at atemperature of the order of 122° C. for 22 hours. Ethanolamine (1.9 g)and lithium chloride (0.1 g) are then added to the reaction mixture andheating is continued for a further 26 hours. After the reaction mixturehas cooled to a temperature of the order of 20° C., solidification isobserved. Ethanol (25 cc) is then added in order to break up thecrystals. After stirring for 30 minutes at a temperature of the order of20° C., the crystals are filtered off, washed twice with ethanol (10 ccin total) and 3 times with isopropyl ether (75 cc in total) and thendried under reduced pressure (20 mm Hg; 2.7 kPa) at a temperature of theorder of 20° C., in the presence of potassium hydroxide pellets. Thisgives a crude product (3.1 g) melting at 150° C. This product isdissolved in boiling ethanol (40 cc). The solution obtained is treatedwith decolourising charcoal (0.5 g) and filtered hot. The filtrate iscooled at a temperature of the order of 40° C. for 1 hour. The crystalswhich have appeared are filtered off, washed twice with ethanol (10 ccin total) and 3 times with isopropyl ether (45 cc) in total and thendried under reduced pressure (20 mm Hg; 2.7 kPa) at a temperature of theorder of 20° C., in the presence of potassium hydroxide pellets. ThisgivesN-]2-(2-hydroxyethyl)-aminoethyl]-5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazole-7-carboxamide(2 g) in the form of pale yellow crystals melting at 163° C.

The 5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazole-7-carbonitrile isprepared as in Example 1.

EXAMPLE 23

A suspension of powdered potassium hydroxide (12.3 g) and a mixture (inthe ratio 20/80) of 6-cyano and7-cyano-3-phenyl-5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazole (11.3 g)in tert.-butyl alcohol (260 cc) is heated under reflux for 3 hours. Thesuspension is stirred for 16 hours at a temperature of the order of 20°C. and is then concentrated to dryness under reduced pressure (20 mm Hg;2.7 kPa) at a temperature of the order of 60° C. The residue obtained issuspended in distilled water (300 cc) and is extracted 3 times withethyl acetate (750 cc in total). The organic extracts are combined,washed 3 times with distilled water (300 cc in total), dried overanhydrous magnesium sulphate, treated with decolourising charcoal (0.5g) and filtered, and the filtrate is concentrated to dryness underreduced pressure (20 mm Hg; 2.7 kPa) at a temperature of the order of60° C. This gives a crude product (9.2 g). This product ischromatographed on a column of diameter 6 cm, containing silica(0.04-0.063 mm) (480 g). Elution is carried out with a mixture of ethylacetate and methanol (95/5 by volume) under a pressure of 0.5 bar (51kPa), 200 cc fractions being collected. The first 10 fractions arediscarded. The next 12 fractions are combined and concentrated todryness under reduced pressure (20 mm Hg; 2.7 kPa) at a temperature ofthe order of 60° C. This gives a product (7 g). This product isdissolved in ethanol (140 cc). The solution obtained is treated with a2N ethanolic solution of hydrogen chloride (3.1 cc) and stirred at atemperature of the order of 20° C. for 15 minutes. The crystals whichhave appeared are filtered off, washed twice with ethanol (50 cc intotal) and 3 times with diethyl ether (75 cc in total) and dried underreduced pressure (20 mm Hg; 2.7 kPa) at a temperature of the order of20° C., in the presence of potassium hydroxide pellets. This gives3-phenyl-5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazole-7-carboxamidehydrochloride (6 g) in the form of yellow crystals melting at 250° C.

The mixture (20/80) of 6-cyano and7-cyano-3-phenyl-5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazole can beprepared in the following manner:

A suspension of N-nicotinoyl-2-phenylthiazolidine-4-carboxylic acid(45.2 g) in a mixture of 2-chloroacrylonitrile (115 cc) and aceticanhydride (180 cc) is heated at a temperature of the order of 90° C. for3 hours and the solution obtained is stirred at a temperature of theorder of 20° C. for 16 hours. The solvent is evaporated off underreduced pressure (20 mm Hg; 2.7 kPa) at a temperature of the order of60° C. and the residue is taken up at a temperature of the order of 4°C. in a mixture of distilled water (300 cc), a 10N aqueous solution ofsodium hydroxide (400 cc) and ethyl acetate (500 cc). The organic phaseis separated off by decantation and the aqueous phase is extracted 3times with ethyl acetate (1,500 cc in total) and 4 times with methylenechloride (2,000 cc in total). The organic extracts are combined, washed4 times with distilled water (1,000 cc in total), dried over anhydrousmagnesium sulphate, treated with decolourising charcoal (0.5 g) andfiltered, and the filtrate is concentratrd to dryness under reducedpressure (20 mm Hg; 2.7 kPa) at a temperature of the order of 60° C.This gives a crude product (33.8 g). This product is chromatographed ona column of diameter 6 cm, containing silica (0.04-0.063 mm) (480 g).Elution is carried out with a mixture of cyclohexane and ethyl acetate(50/50 by volume) under a pressure of 0.5 bar (51 kPa), 100 cc fractionsbeing collected. The first 17 fractions are discarded and the next 14fractions are combined and concentrated to dryness under reducedpressure (20 mm Hg; 2.7 kPa) at a temperature of the order of 60° C.This gives a mixture of 6-cyano and 7-cyano-3 phenyl5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazole (11.3 g), in a ratio of20/80 (according to the NMR spectrum), in the form of a brown oil.

[Rf=0.35 and 0.4; chromatography on a thin layer of silica gel; solvent:cyclohexane/ethyl acetate (50/50 by volume)].

The N-nicotinoyl-2-phenylthiazolidine-4-carboxylic acid can be preparedin the following manner:

Nicotinoyl chloride hydrochloride (88.1 g) is added in the course of 20minutes, at a temperature of between 32° and 54° C., to a solution of2-phenylthiazolidine-4-carboxylic acid (94.2 g) and triethylamine (100g) in chloroform (1,120 cc). The solution obtained is heated at atemperature of the order of 63° C. for 5 hours and is then stirred at atemperature of the order of 20° C. for 16 hours. A product crystallises.The suspension is cooled at a temperature of the order of 4° C. for 1hour. The crystals which have appeared are filtered off, washed 3 timeswith chloroform (300 cc in total) and dried under reduced pressure (20mm Hg; 2.7 kPa) at a temperature of the order of 20° C., in the presenceof potassium hydroxide pellets. This gives a crude product (145 g)melting at 150° C. This product is suspended in distilled water (750cc). The crystals are filtered off, washed 3 times with distilled water(750 cc in total) and dried in air. This gives a product (90.9 g)melting at 182° C. This product (15 g) is dissolved in boiling ethanol(200 cc). The solution obtained is treated with decolourising charcoal(0.5 g) and filtered hot. The filtrate is cooled at a temperature of theorder of 4° C. for 1 hour. The crystals which have appeared are filteredoff, washed twice with ethanol (50 cc in total) and 3 times with diethylether (75 cc in total) and dried under reduced pressure (20 mm Hg; 2.7kPa) at a temperature of the order of 20° C., in the presence ofpotassium hydroxide pellets. This givesN-nicotinoyl-2-phenylthiazolidine-4-carboxylic acid (11.4 g) in the formof white crystals melting at 186° C.

The 2-phenylthiazolidine-4-carboxylic acid can be prepared according toR. RIEMSCHNEIDER and G. A. HOYER, Z. Naturforsch, 17 B, 765 (1962).

EXAMPLE 24

A suspension of powdered potassium hydroxide (20.4 g) and a mixture (inthe ratio 50/50) of 6-cyano and7-cyano-3-methyl-5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazole (17.6 g)in tert.-butyl alcohol (200 cc) is heated under reflux for 1 hour 20minutes. The solvent is evaporated off under reduced pressure (20 mm Hg;2.7 kPa) at a temperature of the order of 50° C. The residue is treatedwith a mixture of distilled water (200 cc) and methylene chloride (100cc). The organic phase is separated off by decantation and the aqueousphase is extracted 4 times with methylene chloride (400 cc in total).The organic extracts are combined, washed 5 times with distilled water(750 cc in total), dried over anhydrous magnesium sulphate and filtered,and the filtrate is concentrated to dryness under reduced pressure (20mm Hg; 2.7 kPa) at a temperature of the order of 50° C. This gives aproduct (19 g). This product is dissolved in methylene chloride (50 cc).Crystals appear; they are filtered off, washed 3 times with methylenechloride (15 cc in total) and dried under reduced pressure (20 mm Hg;2.7 kPa), in the presence of potassium hydroxide pellets. This gives aproduct (6.1 g) melting at 170° C. The filtrate is chromatographed on acolumn of diameter 6 cm, containing silica (0.04-0.063 mm) (480 g).Elution is carried out with mixtures of ethyl acetate and methanol undera pressure of 0.5 bar (51 kPa), 250 cc fractions being collected. Thefirst 13 fractions from elution with a mixture of ethyl acetate andmethanol (97.5/2.5 by volume) are discarded. The next 3 fractions fromelution with a mixture of ethyl acetate and methanol (95/5 by volume)and the next three fractions from elution with a mixture of ethylacetate and methanol (95/5 by volume) are combined and concentrated todryness under reduced pressure (20 mm Hg; 2.7 kPa) at a temperature ofthe order of 50° C. This gives a product (3.1 g), which is combined withthe previously obtained product (6.1 g) and dissolved in boilingisopropanol (90 cc). The solution obtained is treated with decolourisingcharcoal (0.5 g) and filtered hot. The filtrate is cooled at atemperature of the order of 4° C. for 1 hour. The crystals which haveappeared are filtered off, washed 3 times with isopropanol cooled to atemperature of the order of 4° C. (6 cc in total) and 3 times withdiethyl ether (30 cc in total) and dried under reduced pressure (120 mmHg; 2.7 kPa) at a temperature of the order of 20° C., in the presence ofpotassium hydroxide pellets. This gives3-methyl-5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazole-7-carboxamide(5.6 g) in the form of cream crystals melting at 170° C.

The mixture (50/50) of 6-cyano and7-cyano-3-methyl-5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazole can beobtained in the following manner:

A suspension of N-nicotinoyl-2-methylthiazolidine-4-carboxylic acid(36.3 g) in a mixture of 2-chloroacrylonitrile (115 cc) and aceticanhydride (200 cc) is heated at a temperature of the order of 90° C. for3 hours. The solution obtained is concentrated to dryness under reducedpressure (20 mm Hg; 2.7 kPa) at a temperature of the order of 70° C. andthe residue obtained is taken up in distilled water (200 cc). Thesuspension obtained is brought to a pH of the order of 10 by adding a10N aqueous solution of sodium hydroxide (80 cc), the reaction mixturebeing kept at a temperature of the order of 20° C. The suspensionobtained is treated with methylene chloride (250 cc) and stirred at atemperature of the order of 20° C. for 16 hours. The organic phase isseparated off by decantation and the aqueous phase is extracted 5 timeswith methylene chloride (500 cc in total). The organic extracts arecombined and washed 5 times with distilled water (500 cc in total) and 5times with a 2N aqueous solution of hydrochloric acid (400 cc in total).The aqueous phase is separated off be decantation, treated withdecolourising charcoal (0.5 g) and filtered, and the filtrate is broughtto a pH of the order of 10 by adding a 10N aqueous solution of sodiumhydroxide and extracted 5 times with methylene chloride (500 cc intotal). The organic extracts are combined, dried over anhydrousmagnesium sulphate, treated with decolourising charcoal (0.5 g) andfiltered, and the filtrate is concentrated to dryness under reducedpressure (20 mm Hg; 2.7 kPa) at a temperature of the order of 50° C.This gives a crude product (19.3 g). This product is chromatographed ona column of diameter 6 cm, containing silica (0.04-0.063 mm) (480 g).Elution is carried out with a mixture of cyclohexane and ethyl acetate(50/50 by volume) under a pressure of 0.5 bar (51 kPa), 200 cc fractionsbeing collected. The first 8 fractions are discarded and the next 8fractions are combined and concentrated to dryness under reducedpressure (20 mm Hg; 2.7 kPa) at a temperature of the order of 50° C.This gives a mixture of 6-cyano and7-cyano-3-methyl-5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazole (17.6 g),in a ratio of 50/50 (according to the NMR spectrum), in the form of ayellow oil.

[Rf=0.35 and 0.4; chromatography on a thin layer of silica gel; solvent:cyclohexane/ethyl acetate (50/50 by volume)].

The N-nicotinoyl-2-methylthiazolidine-4-carboxylic acid can be preparedin the following manner:

Nicotinoyl chloride hydrochloride (53.4 g) is added in the course of 25minutes, at a temperature of between 20° C. and 47° C., to a suspensionof 2-methylthiazolidine-4-carboxylic acid (44.1 g) and triethylamine(61.8 g) in chloroform (500 cc). The suspension obtained is heated at atemperature of the order of 65° C. for 1 hour 45 minutes and thesolution obtained is then stirred at a temperature of the order of 20°C. for 16 hours. The solvent is evaporated off under reduced pressure(20 mm Hg; 2.7 kPa) at a temperature of the order of 50° C. and theresidue obtained is suspended in acetone (300 cc). After stirring for 2hours at a temperature of the order of 20° C., the crystals which haveappeared are filtered off, washed twice with acetone (400 cc in total)and dried under reduced pressure (20 mm Hg; 2.7 kPa) at a temperature ofthe order of 20° C., in the presence of potassium hydroxide pellets. Thesolid obtained is suspended in distilled water (250 cc) and the crystalswhich have appeared are filtered off, washed 3 times with distilledwater (450 cc in total) and 3 times acetone (60 cc in total) and driedunder reduced pressure (20 mm Hg; 2.7 kPa) at a temperature of the orderof 20° C., in the presence of potassium hydroxide pellets. This givesN-nicotinoyl-2-methylthiazolidine4-carboxylic acid (36.5 g) in the formof cream crystals melting at 190° C.

The 2-methylthiazolidine-4-carboxylic acid can be prepared according toH.T. NAGASAWA, D.J.W. GOON, R.T. ZERA and D.L. YUZON, J. Med. Chem., 25,489 (1982).

EXAMPLE 25

Triethylamine (50.1 g) is added in the course of 15 minutes, at atemperature of the order of 10° C., to a suspension of2-aminoethanethiol hydrochloride (51.1 g) in ethanol (250 cc). Thesuspension obtained is stirred at a temperature of the order of 10° C.for 15 minutes and then filtered. The filtrate is treated with5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazole-7-carbonitrile (20.5 g)and the suspension obtained is heated at the boil for 22 hours. Thesolution obtained is cooled to a temperature of the order of 4° C. andthe crystals which have appeared are filtered off, washed 3 times withethanol cooled to a temperature of the order of 4° C. (75 cc in total)and 4 times with diethyl ether (100 cc in total) and then dried underreduced pressure (20 mm Hg; 2.7 kPa) at a temperature of the order of20° C., in the presence of potassium hydroxide pellets. This gives aproduct (25 g) melting at 136° C. This product is combined with theproduct originating from another earlier operation (1.5 g) and dissolvedin boiling ethanol (400 cc). The solution obtained is treated withdecolourising charcoal (0.5 g) and filtered hot. The filtrate is cooledat a temperature of the order of 4° C. for 1 hour. The crystals whichhave appeared are filtered off, washed 3 times with ethanol (75 cc intotal) and 3 times with diethyl ether (150 cc in total) and dried underreduced pressure (20 mm Hg; 2.7 kPa) at a temperature of the order of20° C., in the presence of potassium hydroxide pellets. This gives aproduct (23 g) melting at 124° C. This product is dissolved in boilingacetonitrile (300 cc). The solution obtained is treated withdecolourising charcoal (0.5 g) and filtered hot. The filtrate is cooledat a temperature of the order of 4° C. for 1 hour. The crystals whichhave appeared are filtered off, washed 3 times with acetonitrile cooledto a temperature of the order of 4° C. (75 cc in total) and 3 times withdiethyl ether (150 cc in total) and then dried under reduced pressure(20 mm Hg; 2.7 kPa) at a temperalure of the order of 20° C., in thepresence of potassium hydroxide pellets. This gives7-(4,5-dihydrothiazol-2-yl)-5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazole(20.1 g) in the form of orange-yellow crystals melting at 124° C.

The 5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazole-7-carbonitrile isprepared as in Example 1.

EXAMPLE 26

A suspension of methyl5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazole-7-carbodithioate (24.85g), ethylenediamine (15.6 g) and mercuric chloride (23.1 g) is heated ata temperature of the order of 78° C. for 3 hours. Mercuric chloride(23.1 g) is then added to the suspension and heating is continued for afurther 17 hours. The suspension is then cooled to a temperature of theorder of 20° C. and the solvent is evaporated off under reduced pressure(20 mm Hg; 2.7 kPa) at a temperature of the order of 60° C. The residueis suspended in water (850 cc) at a temperature of the order of 85° C. A10N aqueous solution of sodium hydroxide (1,200 cc) is added to thissuspension and heating is continued at a temperature of the order of 85°C. for 1 hour, with stirring. The suspension is then cooled to atemperature of the order of 20° C. and the crystals are filtered off andwashed 4 times with distilled water (1,000 cc in total). The crystalsthus obtained are suspended in boiling chloroform (1,000 cc) and thesuspension is filtered hot. The same operation is repeated twice. Thefiltrates are combined, dried over anhydrous magnesium sulphate, treatedwith decolourising charcoal (0.5 g) and filtered, and the filtrate isconcentrated to dryness under reduced pressure (20 mm Hg; 2.7 kPa) at atemperature of the order of 60° C. This gives a crude product (18.4 g)melting at 184° C. This product is dissolved in boiling isopropanol (200cc). The solution obtained is treated with decolourising charcoal (0.5g) and filtered hot. The filtrate is cooled at a temperature of theorder of 4° C. for 3 days. The crystals which have appeared are filteredoff, washed twice with isopropanol (30 cc in total) and 3 times withdiethyl ether (75 cc in total) and then dried under reduced pressure (20mm Hg; 2.7 kPa) at a temperature of the order of 20° C., in the presenceof potassium hydroxide pellets. This gives7-(.increment.2-imidazolin-2-yl)-5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazole(10.1 g) in the form of beige crystals melting at 188° C.

The methyl5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]-thiazole-7-carbodithioate can beprepared in the following manner:

S-Methyl5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]-thiazole-7-thiocarboximidatehydroiodide (85.3 g) is added to pyridine (950 cc) saturated at atemperature of the order of 15° C. with a gaseous stream of hydrogensulphide. The suspension obtained is stirred at a temperature of theorder of 20° C. for 16 hours and is then poured into distilled water(6,000 cc). The crystals which have appeared are filtered off, washed 6times with distilled water (1,500 cc in total) and then dissolved inboiling acetonitrile (4,000 cc). The solution obtained is treated withdecolourising charcoal (0.5 g) and filtered hot. The filtrate is cooledat a temperature of the order of 4° C. for 16 hours. The crystals whichhave appeared are filtered off, washed 3 times with acetonitrile (750 ccin total) and 3 times with diethyl ether (750 cc in total) and thendried under reduced pressure (20 mm Hg; 2.7 kPa) at a temperature of theorder of 20° C., in the presence of potassium hydroxide pellets. Thisgives methyl5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazole-7-carbodithioate (44.7 g)in the form of orange-yellow crystals melting at 158° C.

The S-methyl5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2c-]thiazole-7-carboximidatehydroiodide is prepared as in Example 8.

EXAMPLE 27

Phosphoryl chloride (16.4 g) is added in the course of 10 minutes, at atemperature of the order of 10° C., to dimethylformamide (55 cc). Thesolution obtained is added dropwise in the course of 25 minutes, withstirring, at a temperature of the order of 4° C., to a solution of5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazole (14.4 g) indimethylformamide (130 cc). The solution obtained is stirred at atemperature of the order of 20° C. for 16 hours. Crystals appear. A 2Naqueous solution of sodium hydroxide (215 cc) is then added to thesuspension obtained; the solution obtained is poured into distilledwater (2,150 cc) and extracted 3 times with ethyl acetate (1,800 cc intotal). The organic extracts are combined, washed 5 times with distilledwater (2,000 cc in total), dried over anhydrous magnesium sulphate,treated with decolourising charcoal (0.5 g) and filtered, and thefiltrate is concentrated to dryness under reduced pressure (20 mm Hg;2.7 kPa) at a temperature of the order of 60° C. This gives a crudeproduct (13.4 g). This product is dissolved in boiling ethanol (120 cc).The solution obtained is cooled at a temperature of the order of 4° C.for 2 hours. The crystals which have appeared are filtered off, washedtwice with ethanol cooled to a temperature of the order of 4° C. (20 ccin total) and then 3 times with isopropyl ether (150 cc in total) anddried under reduced pressure (20 mm Hg; 2.7 kPa) at a temperature of theorder of 20° C., in the presence of potassium hydroxide pellets. Thisgives a product (7.4 g) melting at 104° C. This product is combined withthe product prepared in the same way in another earlier operation (3 g)and is dissolved in boiling ethanol (60 cc). The solution obtained istreated with decolourising charcoal (0.5 g) and filtered hot. Thefiltrate is cooled at a temperature of the order of 4° C. for 2 hours.The crystals which have appeared are filtered off, washed 3 times withethanol cooled to a temperature of the order of 4° C. (15 cc in total)and 3 times with isopropyl ether (75 cc in total) and then dried underreduced pressure (20 mm Hg; 2.7 kPa) at a temperature of the order of20° C., in the presence of potassium hydroxide pellets. This gives5-(pyridin-3-yl)-1H,3H-pyrrolol[1,2-c]thiazole-7-carboxaldehyde (7.9 g)in the form of light beige crystals melting at 104° C.

The 5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazole is prepared in thefollowing manner:

A mixture of 5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2c-]thiazole-7-carboxylicacid (36.9 g) and copper powder (1.8 g) is heated at a temperature ofthe order of 250° C. for 30 minutes. The reaction mixture is cooled to atemperature of the order of 20° C. and is then taken up in methylenechloride (500 cc). The suspension obtained is washed twice with a 2Naqueous solution of sodium hydroxide (200 cc in total) and filtered. Theorganic phase is decanted and washed 3 times with distilled water (300cc in total), dried over anhydrous magnesium sulphate, treated withdecolourising charcoal (0.5 g) and filtered, and the filtrate isconcentrated to dryness under reduced pressure (20 mm Hg; 2.7 kPa) at atemperature of the order of 60° C. This gives a crude product (25.3 g).This product is chromatographed on a column of diameter 4 cm, containingsilica (0.063-0.2 mm) (250 g), elution being carried out with a mixtureof cyclohexane and ethyl acetate (50/50 by volume), 600 cc fractionsbeing collected. The first fraction is discarded and the next two arecombined and concentrated to dryness under reduced pressure (20 mm Hg;2.7 kPa) at a temperature of the order of 60° C. This gives5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazole (21.3 g) in the form oforange crystals melting at 74 ° C.

The 5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazole-7-carboxylic acid isprepared as in Example 3.

EXAMPLE 28

Methanesulphonic acid (14.4 g) is added to a solution of5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazole-7-carboxamide (36.8 g) inacetic acid (500 cc). A solution of 85% pure (by weight)3-chloroperbenzoic acid (67 g) in methylene chloride (1,000 cc) is addeddropwise to the solution obtained in the course of 40 minutes, at atemperature of the order of 20° C. The solution obtained is stirred at atemperature of the order of 20° C. for 16 hours and the reaction mixtureis then added in the course of 2 hours 30 minutes to a 10N aqueoussolution of sodium hydroxide (1,200 cc), the temperature of the reactionmixture being kept at about 20° C. The solid which has appeared isfiltered off, washed 4 times with a mixture of chloroform and methanol(80/20 by volume) (4,000 cc in total), 4 times with distilled water(1,000 cc in total) and 3 times with acetone (300 cc in total) and thendried under reduced pressure (20 mm Hg; 2.7 kPa) at a temperature of theorder of 20° C., in the presence of potassium hydroxide pellets. Thisgives a product (24.8 g). The filtrate and the mother liquors from theprevious washings are combined; the organic phase is decanted, driedover anhydrous magnesium sulphate, treated with decolourising charcoal(0.5 g) and filtered, and the filtrate is concentrated to dryness underreduced pressure (20 mm Hg; 2.7 kPa) at a temperature of the order of50° C. This gives a product (17.6 g). This product is suspended indistilled water (150 cc) and the crystals are filtered off, washed 3times with distilled water (75 cc in total) and 3 times with acetone (75cc in total) and then dried under reduced pressure (20 mm Hg; 2.7 kPa)at a temperature of the order of 20° C., in the presence of potassiumhydroxide pellets. The product thus obtained (3.3 g) is combined withthe previously isolated product (24.8 g) and is dissolved in a boiling2N aqueous solution of acetic acid (1,000 cc). The solution obtained istreated with decolourising charcoal (0.5 g) and filtered hot. Thefiltrate is cooled at a temperature of the order of 4° C. for 3 hours.The crystals which have appeared are filtered off, washed twice with a2N aqueous solution of acetic acid (100 cc in total), 3 times withdistilled water (300 cc in total), 3 times with ethanol (150 cc intotal) and 3 times with diethyl ether (150 cc in total) and then driedunder reduced pressure (20 mm Hg; 2.7 kPa) at a temperature of the orderof 20° C., in the presence of potassium hydroxide pellets. This gives5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazole-7-carboxamide 2,2-dioxide(17 g) in the form of pale yellow crystals melting at 264° C.

The 5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazole-7-carboxamide can beprepared as described in Example 1.

EXAMPLE 29

A solution of ethyl6-{[5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazol-7-yl]-carbonylamino}-hexanoate(2.9 g) in a mixture of a 2N aqueous solution of sodium hydroxide (7.5cc) and ethanol (30 cc) is stirred at a temperature of the order of 20°C. for 16 hours. The solution is then concentrated to dryness underreduced pressure (20 mm Hg; 2.7 kPa) at a temperature of the order of60° C. The residue obtained is dissolved in water (50 cc) and thesolution obtained is brought to a pH of the order of 3 by adding a 0.5Naqueous solution of hydrochloric acid (40 cc). The crystals which haveappeared are filtered off, washed 5 times with distilled water (150 ccin total), 3 times with acetone (45 cc in total) and then twice withdiethyl ether (30 cc in total) and dried under reduced pressure (20 mmHg; 2.7 kPa) at a temperature of the order of 20° C., in the presence ofpotassium hydroxide pellets. This gives a crude product (2 g) melting at152° C. This product is dissolved in boiling ethanol (40 cc). Thesolution obtained is treated with decolourising charcoal (0.5 g) andfiltered hot. The filtrate is cooled at a temperature of the order of 4°C. for 3 hours. The crystals which have appeared are filtered off,washed twice with ethanol (10 cc in total) and then 3 times with diethylether (30 cc in total) and dried under reduced pressure (20 mm Hg; 2.7kPa) at a temperature of the order of 20° C., in the presence ofpotassium hydroxide pellets. This gives6-{[5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazol-7-yl]-carbonylamino}-hexanoicacid (1.5 g) in the form of cream crystals melting at 158° C.

The ethyl6-{[5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazol-7-yl]-carbonylamino}-hexanoateis prepared in the following manner:

A solution of ethyl 6-aminohexanoate (4.1 g) and triethylamine (5.3 g)in methylene chloride (45 cc) is added in the course of 10 minutes, at atemperature of between 22° C. and 32° C., to a suspension of7-chloroformyl-5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazolehydrochloride (7.8 g) in methylene chloride (130 cc). The solutionobtained is stirred at a temperature of the order of 20° C. for 16 hoursand is then diluted with methylene chloride (150 cc), washed 4 timeswith distilled water (800 cc in total), dried over anhydrous magnesiumsulphate, treated with decolourising charcoal (0.5 g) and filtered, andthe filtrate is concentrated to dryness under reduced pressure (20 mmHg; 2.7 kPa) at a temperature of the order of 60° C. This gives a crudeproduct (9.3 g). This product is chromatographed on a column of diameter3 cm, containing silica (0.063-0.2 mm) (100 g), elution being carriedout with mixtures of ethylene chloride and ethanol and 300 cc fractionsbeing collected. The first three fractions from elution with puremethylene chloride and the next 2 fractions from elution with a mixtureof methylene chloride and methanol (98/2 by volume) are discarded andthe next 2 fractions from elution with a mixture of methylene chlorideand methanol (98/2 by volume) and the next fraction from elution with amixture of methylene chloride and methanol (96/4 by volume) are combinedand concentrated to dryness under reduced pressure (20 mm Hg; 2.7 kPa)at a temperature of the order of 60° C. This gives ethyl6-{[5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazol-7-yl]carbonylamino}-hexanoate(2.9 g) in the form of a brown oil.

[Rf=0.55; chromatography on a thin layer of silica gel; solvent:methylene chloride/methanol (90/10 by volume)].

The ethyl 6-aminohexanoate can be prepared according to C. S. MARVEL,J.R. ELLIOTT, F. E. BOETTNER and H. YUSKA, J. Amer. Chem. Soc., 68, 1681(1946).

EXAMPLE 30

A suspension of3-(pyridin-3-yl)-5,6,7,8-tetrahydroindolizine-1-carbonitrile (5.2 g) andpowdered potassium hydroxide (7.7 g) in tert.-butyl alcohol (120 cc) isheated for 13 hours at a temperature on the order of 80° C. Thesuspension is then concentrated to dryness under reduced pressure (20 mmHg; 2.7 kPa) at a temperature of the order of 60° C. The residue istaken up in distilled water (200 cc) and the suspension obtained isstirred at a temperature of the order of 20° C. for 1 hour. The crystalswhich have appeared are filtered off, washed 5 times with distilledwater (250 cc in total) and dried under reduced pressure (20 mm Hg; 2.7kPa) at a temperature of the order of 20° C., in the presence ofpotassium hydroxide pellets. This gives a crude product (4.1 g) meltingat 180° C. This product, combined with the product prepared in the sameway in another operation (1.1 g), is dissolved in boiling acetonitrile(160 cc). The turbid solution obtained is treated with decolourisingcharcoal (0.5 g) and filtered hot. The filtrate is cooled at atemperature of the order of 4° C. for 2 hours. The crystals which haveappeared are filtered off, washed 3 times with acetonitrile (75 cc intotal) and 3 times with isopropyl ether (75 cc in total) and then driedunder reduced pressure (20 mm Hg; 2.7 kPa) at a temperature of the orderof 20° C., in the presence of potassium hydroxide pellets. This gives3-(pyridin-3-yl)-5,6,7,8-tetrahydroindolizine-1-carboxamide (4 g) in theform of light beige crystals melting at 184° C.

The 3-(pyridin-3-yl)-5,6,7,8-tetrahydroindolizine-1-carbonitrile can beprepared in the following manner:

A suspension of N-nicotinoylpiperidine-2-carboxylic acid (14.7 g) in amixture of 2-chloroacrylonitrile (50 cc) and acetic anhydride (65 cc) isheated at a temperature of the order of 90° C. for 4 hours. Afterstirring for 16 hours at a temperature of the order of 20° C., thecrystals are filtered off, washed 3 times with acetic anhydride (75 ccin total) and dried under reduced pressure (20 mm Hg; 2.7 kPa) at atemperature of the order of 20° C., in the presence of potassiumhydroxide pellets. The product thus obtained (10 g) is dissolved indistilled water (100 cc). After the addition of a 10N aqueous solutionof sodium hydroxide (50 cc) at a temperature of the order of 10° C., asuspension is obtained, which is stirred at a temperature of the orderof 20° C. for 1 hour and then extracted 3 times with ethyl acetate (450cc in total). The organic extracts are combined, washed 3 times withdistilled water (300 cc in total), dried over anhydrous magnesiumsulphate, treated with decolourising charcoal (0.5 g) and filtered, andthe filtrate is concentrated to dryness under reduced pressure (20 mmHg; 2.7 kPa) at a temperature of the order of 60° C. This gives aproduct (8.8 g), which is chromatographed on a column of diameter 6 cm,containing silica (0.04-0.063 mm) (480 g), elution being carried outwith ethyl acetate under a pressure of 0.5 bar (51 kPa) and 100 ccfractions being collected. The first 14 fractions are discarded and thenext 6 fractions are combined and concentrated to dryness under reducedpressure (20 mm Hg; 2.7 kPa) at a temperature of the order of 60° C.This gives 3-(pyridin-3-yl)-5,6,7,8-tetrahydroindolizine-1-carbonitrile(5.2 g) in the form of brown crystals melting at 112° C.

The N-nicotinoylpiperidine-2-carboxylic acid can be prepared in thefollowing manner:

A solution of ethyl N-nicotinoylpiperidine-2-carboxylate (34.1 g) in amixture of a 2N aqueous solution of sodium hydroxide (130 cc) andethanol (325 cc) is stirred at a temperature of the order of 20° C. for16 hours. The solvent is then evaporated off under reduced pressure (20mm Hg; 2.7 kPa) at a temperature of the order of 60° C. The residueobtained is dissolved in distilled water (250 cc). The turbid solutionobtained is treated with decolourising charcoal (0.5 g) and filtered.The filtrate, kept at a temperature of 20° C., is brought to a pH of theorder of 3 by adding a 4N aqueous solution of hydrochloric acid (80 cc).The suspension obtained is stirred at a temperature of the order of 20°C. for 1 hour and the crystals are filtered off, washed 4 times withdistilled water (200 cc in total), 3 times with acetone (150 cc intotal) and once with diethyl ether (50 cc) and then dried under reducedpressure (20 mm Hg; 2.7 kPa) at a temperature of the order of 20° C., inthe presence of potassium hydroxide pellets. This givesN-nicotinoylpiperidine-2-carboxylic acid (14.8 g) in the form of whitecrystals melting at 194° C.

The ethyl N-nicotinoylpiperidine-2-carboxylate can be prepared in thefollowing manner:

Triethylamine (182 g) is initially added, at a temperature of between20° C. and 31° C., to a solution of ethyl piperidine-2-carboxylate (72.9g) in chloroform (1,120 cc), this being followed, in the course of 35minutes, at a temperature of between 26° C. and 50° C., by nicotinoylchloride hydrochloride (160.2 g). The suspension obtained is stirred ata temperature of the order of 20° C. for 16 hours and then washed 5times with distilled water (1,500 cc in total), dried over anhydrousmagnesium sulphate, treated with decolourising charcoal (0.5 g) andfiltered, and the filtrate is concentrated to dryness under reducedpressure (20 mm Hg; 2.7 kPa) at a temperature of the order of 60° C.This gives a crude product (174 g), which is chromatographed on a columnof diameter 8 cm, containing silica (0.063-0.2 mm) (1,740 g), elutionbeing carried out with mixtures of cyclohexane and ethyl acetate and1,000 cc fractions being collected. The first 5 fractions from elutionwith a mixture of cyclohexane and ethyl acetate (80/20 by volume), thenext 5 fractions from elution with a mixture of cyclohexane and ethylacetate (70/30 by volume), the next 7 fractions from elution with amixture of cyclohexane and ethyl acetate (60/40 by volume) and the nextfraction from elution with a mixture of cyclohexane and ethyl acetate(50/50 by volume) are discarded. The next 8 fractions from elution witha mixture of cyclohexane and ethyl acetate (50/50 by volume) and thenext 7 fractions from elution with pure ethyl acetate are combined andconcentrated to dryness under reduced pressure (20 mm Hg; 2.7 kPa) at atemperature of the order of 60 ° C. This gives ethylN-nicotinoylpiperidine-2-carboxylate (99.3 g) in the form of an orangeoil.

(Rf=0.46; chromatography on a thin layer of silica gel; eluent: ethylacetate).

The present invention also provides pharmaceutical compositionscomprising a compound of the formula (I), in the free form or in theform of an addition salt with a pharmaceutically acceptable acid orbase, and a compatible pharmaceutical carrier (which may be a coating).The said carrier is normally inert but may be, or contain, aphysiologically active ingredient. The compositions of the invention canbe made up in a form suitable for oral, parenteral, rectal or topicaladministration.

Tablets, pills, powders (in particular in gelatine capsules or incachets) and granules are examples of solid compositions for oraladministration. In these compositions, the active compound of theinvention may be mixed with one or more inert diluents such as starch,cellulose, sucrose, lactose or silica. These compositions can alsocomprise carriers other than diluents, e.g. one or more adjuvants,including lubricants such as magnesium stearate or talc, a colorant, acoating (coated tablets) or a lacquer.

Solutions, suspensions, emulsions, syrups and pharmaceuticallyacceptable elixirs containing inert diluents such as water, ethanol,glycerol, vegetable oils or paraffin oil are examples of liquidcompositions for oral administration. These compositions can comprisesubstances in addition to diluents, e.g. wetting, sweetening,thickening, flavouring or stabilising agents.

Sterile compositions for parenteral administration are preferablysuspensions, emulsions or aqueous or nonaqueous solutions. Water,propylene glycol, a polyethylene glycol, vegetable oils, in particularolive oil, injectable organic esters, e.g. ethyl oleate, or othersuitable organic solvents can be employed as the solvent or vehicle.These compositions can also contain adjuvants, in particular wettingagents, agents for imparting isotonicity, emulsifiers, dispersing agentsand stabilisers. Sterilisation can be carried out in several ways, e.g.by filtration under aseptic conditions, by incorporating sterilisingagents into the composition, by irradiation or by heating. Thecompositions can also be prepared in the form of sterile solidcompositions which are dissolved in an injectable sterile medium at thetime of use.

Compositions for rectal administration are suppositories or rectalcapsules, which contain, in addition to the active compound, excipientssuch as cocoa butter, semi-synthetic glycerides or polyethylene glycols.

Compositions for topical administration can be, e.g. creams, ointments,lotions, eye lotions, mouthwashes, nose drops or aerosols.

In human therapy, the compounds of the invention are particularly usefulin the prophylactic and therapeutic treatment of thrombotic complaints.The doses depend on the desired effect and the duration of thetreatment. For an adult, a dosage of generally between 100 and 1,000 mgper day, administered orally in one or more individual doses, or ofbetween 10 and 100 mg, administered parenterally in one or moreinjections, is generally suitable.

The physician will determine the dosage which he considers to be mostappropriate as a function of the age, the weight and all the otherfactors peculiar to the patient to be treated.

The Examples which follow illustrate compositions according to theinvention.

EXAMPLE A

Tablets containing 200 mg doses of active ingredient and having thefollowing composition are prepared by the usual technique:

    ______________________________________                                        5-(pyridin-3-yl)-1H,3H--pyrrolo[1,2-c]                                                               200 mg                                                 thiazole-7-carboxamide                                                        starch                 60 mg                                                  lactose                50 mg                                                  magnesium stearate      2 mg                                                  ______________________________________                                    

EXAMPLE B

An injectable solution containing 20 mg of active product and having thefollowing composition is prepared:

    ______________________________________                                        6-(pyridin-3-yl)-1,2-dihydro-4H-                                                                        20     mg                                           pyrrolo[1,2-c]-1,3-thiazine-8-carboxamide                                     0.1 N methanesulphonic acid                                                                             0.77   cc                                           injectable solution q.s.  2      cc                                           ______________________________________                                    

We claim:
 1. A heterocyclic compound of the formula: ##STR26## which Arepresents --S--, --SO--, or --SO₂ --, R₃ represents hydrogen, alkyl orphenyl unsubstituted or substituted by halogen, alkyl, alkoxy ortrifluoromethyl, and(a) X represents oxygen, sulphur, imino orhydroxyamino p represents 0 or 1 and Y represents a radical of theformula: ##STR27## in which R₁ and R₂ both represent hydrogen, or R₁represents hydrogen and R₂ represents hydroxyl or alkyl of 1 to 5 carbonatoms, which is substituted by a carboxyl, amino, alkylamino,dialkylamino, hydroxyalkyl-amino, morpholino or imidazolyl, apiperazin-1-yl radical (unsubstituted or substituted in the 4-positionby alkyl, benzyl optionally substituted by halogen, alkyl, alkoxy ortrifluoromethyl, or phenyl optionally substituted by halogen, alkyl,alkoxy or trifluoromethyl) or a piperidino or pyrrolidin-1-yl radical,or R₂ represents phenyl substituted by one or more hydroxyl, carboxyl,amino, alkylamino or dialkylamino radicals, or R₁ and R₂ form, with thenitrogen atom to which they are bonded, a piperazino, piperidino, ormorpholino ring which is unsubstituted or substituted by alkyl,alkoxycarbonyl, hydroxyalkyl, aminoalkyl, alkylaminoalkyl ordialkylaminoalkyl, a benzyl radical (optionally substituted by a halogenatom or an alkyl, alkoxy or trifluoromethyl radical) or a pyrrolin-1-ylcarbonylalkyl radical, or (b) X represents dialkylhydrazono, Yrepresents amino and p represents 0 or 1, or (c) X and Y form with thecarbon atom to which they are bonded, a Δ2-thiazolin-2-yl orΔ2-imidazolin-2-yl radical and p represents 0 or 1, or (d) X representsoxygen, Y represents hydrogen and p is 0,the said alkyl radicals andalkyl portions being straight-chain or branched-chain and, unless statedotherwise, containing 1 to 4 carbon atoms each, and the tautomeric formsof the compounds where X represents imino, hydroxyimino ordialkylhydrazono and Y represents a radical of the formula (II) in whichR₁ represents a hydrogen atom, or where X represents oxygen of sulphurand Y represents a radical of the general formula (II) in which R₁represents hydrogen and R₂ represents hydroxyl; and its addition saltswith acids and, where they exist, its metal salts and its addition saltswith nitrogen-containing bases.
 2. A heterocyclic compound according toclaim 1, in which A is --S--, --SO₂ -- or --CH₂, R₃ is hydrogen, X isoxygen, sulphur, imino, or hydroxyimino, p is 0 or 1 and Y is a radicalof formula: ##STR28## in which R₁ and R₂ are both hydrogen or R₁ ishydrogen and R₂ is hydroxy or dialkylaminoethyl, or R₁ and R₂ togetherwith the nitrogen atom to which they are attached represent apiperazino, piperidino, or morpholino ring which is unsubstituted orsubstituted by alkyl or benzyl, or X represents dialkylhydrazono, Y isamino, and p is 0, or the radical -C(:X)Y is Δ2-thiazolin-2-yl or --CHOand p is
 0. 3. A hetrocyclic compound according to claim 1 in which A is--S--, or SO₂, R₃ is hydrogen, p is 0, X is oxygen, sulphur, orhydroxymino, and Y is amino, piperazin-1-yl, or 4methyl-piperazin-1-yl,or X is dialkylhydrazono, and Y is amino.
 4. A compound according toclaim 1 which is5-(pyridin-3-yl)-1H,3H-pyrrolo-[1,2-c]thiazole-7-carboxamide and itspharmaceutically acceptable salts.
 5. A compound according to claim 1which is 5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazole-7-carbothioamideand its pharmaceutically acceptable salts.
 6. A compound according toclaim 1 which is5-(pyridin-3-yl)-1H,3H-pyrrolo-[1,2-c]thiazole-7-carboxamide 2,2-dioxideand its pharmaceutically acceptable salts.
 7. A compound according toclaim 1 which is7-(4-methylpiperazin-1-yl)-carbonyl-5-(pyridin-3-yl)-1H,3H-pyrrolo [1,2-c ], thiazole and its pharmaceutically acceptable salts.
 8. A compoundaccording to claim 1 which is5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]-thiazole-7-carboxamide-oxime andits pharmaceutically acceptable salts.
 9. A compound according to claim1 which is5-pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazole-7-carboxamide-dimethylhydrazoneand its pharmaceutically acceptable salts.
 10. A compound according toclaim 1 which is7-(piperazin-1-yl-carbonyl)-5-(pyridin-3-yl)-1H,3H-pyrrolo[1,2-c]thiazoleand its pharmaceutically acceptable salts.
 11. A pharmaceuticalcomposition useful for the prophylactic or therapeutic treatment ofthrombotic complaints comprising an effective amount of at least onecompound according to claim 1, in the free form or in the form of anaddition salt with a pharmaceutically acceptable acid base, inassociation with one or more compatible pharmaceutically acceptablecarriers.
 12. A method for the prophylactic or therapeutic treatment ofthrombotic complaints which comprises administering to a subject in needof such treatment an effective amount of a compound according to claim 1in the free form or in the form of an addition salt whichpharmaceutically acceptable acid or base.